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Interactions between Acetaminophen / caffeine / dihydrocodeine and Felbamate

3 drug interactions and 67 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

acetaminophen felbamate

Applies to: acetaminophen / caffeine / dihydrocodeine and felbamate
Monitor

Coadministration of acetaminophen with other potentially hepatotoxic agents may increase the risk of liver injury. The mechanism may involve additive hepatotoxic effects and, for some medicines, increased formation of hepatotoxic acetaminophen metabolites due to induction of hepatic enzymes. Therapeutic-dose acetaminophen-induced hepatotoxicity, including fatal cases, has been reported in patients with factors associated with increased hepatotoxicity risk, including concomitant use of hepatotoxic drugs, low body weight, renal or hepatic impairment, chronic alcoholism, and malnutrition or other conditions associated with glutathione depletion.

Management

Caution is advised when acetaminophen is used with other potentially hepatotoxic agents, particularly in patients with additional risk factors for hepatotoxicity. Alternative therapy may be considered when appropriate. Patients should not exceed the recommended acetaminophen dosage or use multiple acetaminophen-containing products concurrently. Patients should be monitored for clinical signs and symptoms of liver injury, and liver function monitoring may be appropriate in patients receiving prolonged or high-dose therapy or those at increased risk of hepatotoxicity. If liver injury is suspected, paracetamol should be discontinued and the patient evaluated promptly.

References (5)
  1. (2025) "Product Information. Anadin Paracetamol (paracetamol)." Haleon UK Trading Ltd
  2. (2025) "Product Information. Mersynonight (diphenhydramine-paracetamol)." Sanofi-Aventis Healthcare Pty Ltd T/A Sanofi Consumer Healthcare
  3. (2023) "Product Information. Acetaminophen (acetaminophen)." B. Braun of Canada Ltd
  4. (2026) "Product Information. Acetaminophen (acetaminophen)." Marlex Pharmaceuticals
  5. (2025) "Product Information. ANTIDOL INFANTIL (paracetamol)." LABORATORIOS CINFA, S.A.
Moderate:

dihydrocodeine felbamate

Applies to: acetaminophen / caffeine / dihydrocodeine and felbamate
Monitor

Central nervous system- and/or respiratory-depressant effects may be additively or synergistically increased in patients taking multiple drugs that cause these effects, especially in elderly or debilitated patients. Sedation and impairment of attention, judgment, thinking, and psychomotor skills may increase.

Management

During concomitant use of these drugs, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression. Cautious dosage titration may be required, particularly at treatment initiation. Ambulatory patients should be counseled to avoid hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

References (36)
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  2. Stambaugh JE, Lane C (1983) "Analgesic efficacy and pharmacokinetic evaluation of meperidine and hydroxyzine, alone and in combination." Cancer Invest, 1, p. 111-7
  3. Sotaniemi EA, Anttila M, Rautio A, et al. (1981) "Propranolol and sotalol metabolism after a drinking party." Clin Pharmacol Ther, 29, p. 705-10
  4. Grabowski BS, Cady WJ, Young WW, Emery JF (1980) "Effects of acute alcohol administration on propranolol absorption." Int J Clin Pharmacol Ther Toxicol, 18, p. 317-9
  5. Lemberger L, Rowe H, Bosomworth JC, Tenbarge JB, Bergstrom RF (1988) "The effect of fluoxetine on the pharmacokinetics and psychomotor responses of diazepam." Clin Pharmacol Ther, 43, p. 412-9
  6. MacLeod SM, Giles HG, Patzalek G, Thiessen JJ, Sellers EM (1977) "Diazepam actions and plasma concentrations following ethanol ingestion." Eur J Clin Pharmacol, 11, p. 345-9
  7. Divoll M, Greenblatt DJ, Lacasse Y, Shader RI (1981) "Benzodiazepine overdosage: plasma concentrations and clinical outcome." Psychopharmacology (Berl), 73, p. 381-3
  8. Naylor GJ, McHarg A (1977) "Profound hypothermia on combined lithium carbonate and diazepam treatment." Br Med J, 2, p. 22
  9. Stovner J, Endresen R (1965) "Intravenous anaesthesia with diazepam." Acta Anaesthesiol Scand, 24, p. 223-7
  10. Driessen JJ, Vree TB, Booij LH, van der Pol FM, Crul JF (1984) "Effect of some benzodiazepines on peripheral neuromuscular function in the rat in-vitro hemidiaphragm preparation." J Pharm Pharmacol, 36, p. 244-7
  11. Feldman SA, Crawley BE (1970) "Interaction of diazepam with the muscle-relaxant drugs." Br Med J, 1, p. 336-8
  12. Ochs HR, Greenblatt DJ, Verburg-Ochs B (1984) "Propranolol interactions with diazepam, lorazepam and alprazolam." Clin Pharmacol Ther, 36, p. 451-5
  13. Desager JP, Hulhoven R, Harvengt C, Hermann P, Guillet P, Thiercelin JF (1988) "Possible interactions between zolpidem, a new sleep inducer and chlorpromazine, a phenothiazine neuroleptic." Psychopharmacology (Berl), 96, p. 63-6
  14. Tverskoy M, Fleyshman G, Ezry J, Bradley EL, Jr Kissin I (1989) "Midazolam-morphine sedative interaction in patients." Anesth Analg, 68, p. 282-5
  15. "Product Information. Iopidine (apraclonidine ophthalmic)." Alcon Laboratories Inc
  16. Greiff JMC, Rowbotham D (1994) "Pharmacokinetic drug interactions with gastrointestinal motility modifying agents." Clin Pharmacokinet, 27, p. 447-61
  17. Greb WH, Buscher G, Dierdorf HD, Koster FE, Wolf D, Mellows G (1989) "The effect of liver enzyme inhibition by cimetidine and enzyme induction by phenobarbitone on the pharmacokinetics of paroxetine." Acta Psychiatr Scand, 80 Suppl, p. 95-8
  18. Markowitz JS, Wells BG, Carson WH (1995) "Interactions between antipsychotic and antihypertensive drugs." Ann Pharmacother, 29, p. 603-9
  19. (2001) "Product Information. Ultram (tramadol)." McNeil Pharmaceutical
  20. (2001) "Product Information. Artane (trihexyphenidyl)." Lederle Laboratories
  21. (2001) "Product Information. Ultiva (remifentanil)." Mylan Institutional (formally Bioniche Pharma USA Inc)
  22. (2001) "Product Information. Seroquel (quetiapine)." Astra-Zeneca Pharmaceuticals
  23. (2001) "Product Information. Meridia (sibutramine)." Knoll Pharmaceutical Company
  24. (2001) "Product Information. Tasmar (tolcapone)." Valeant Pharmaceuticals
  25. Miller LG (1998) "Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions." Arch Intern Med, 158, p. 2200-11
  26. (2001) "Product Information. Precedex (dexmedetomidine)." Abbott Pharmaceutical
  27. (2001) "Product Information. Trileptal (oxcarbazepine)." Novartis Pharmaceuticals
  28. Ferslew KE, Hagardorn AN, McCormick WF (1990) "A fatal interaction of methocarbamol and ethanol in an accidental poisoning." J Forensic Sci, 35, p. 477-82
  29. Plushner SL (2000) "Valerian: valeriana officinalis." Am J Health Syst Pharm, 57, p. 328-35
  30. (2002) "Product Information. Xatral (alfuzosin)." Sanofi-Synthelabo Canada Inc
  31. (2002) "Product Information. Lexapro (escitalopram)." Forest Pharmaceuticals
  32. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  33. Cerner Multum, Inc. "Australian Product Information."
  34. (2012) "Product Information. Fycompa (perampanel)." Eisai Inc
  35. (2014) "Product Information. Belsomra (suvorexant)." Merck & Co., Inc
  36. (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka America Pharmaceutical, Inc.

Minor drug interactions

Minor:

acetaminophen dihydrocodeine

Applies to: acetaminophen / caffeine / dihydrocodeine and acetaminophen / caffeine / dihydrocodeine

Narcotic analgesics, anticholinergic agents, and/or agents with anticholinergic properties may delay and/or decrease the gastrointestinal absorption of acetaminophen (paracetamol) by reducing gastric motility and delaying gastric emptying. Available data suggest the clinical impact is minimal and generally does not necessitate dose adjustment.

References (6)
  1. Nimmo J, Heading RC, Tothill P, Prescott LF (1973) "Pharmacological modification of gastric emptying: effects of propantheline and metoclopramide on paracetamol absorption." Br Med J, 1, p. 587-9
  2. Clark JM, Seager SJ (1983) "Gastric emptying following premedication with glycopyrrolate or atropine." Br J Anaesth, 55, p. 1195-9
  3. "Product Information. Transderm-Scop (scopolamine)." Ciba Self-Medication Inc
  4. (2025) "Product Information. Mersynonight (diphenhydramine-paracetamol)." Sanofi-Aventis Healthcare Pty Ltd T/A Sanofi Consumer Healthcare
  5. nimmo ws, Heading RC, Wilson J, Tothill P, Prescott LF (1975) "Inhibition of gastric emptying and drug absorption by narcotic analgesics." Br J Clin Pharmacol, 2, p. 509-13
  6. Heading RC, Nimmo J, Prescott LF, Tothill P (1973) "The dependence of paracetamol absorption on the rate of gastric emptying." Br J Pharmacol, 47, p. 415-21

Food/lifestyle interactions

Major food/lifestyle interactions

Major:

acetaminophen Food/Lifestyle

Applies to: acetaminophen / caffeine / dihydrocodeine
Generally avoid

Chronic, excessive consumption of alcohol may increase the risk of acetaminophen-induced hepatotoxicity, which has included rare cases of fatal hepatitis and frank hepatic failure requiring liver transplantation. The proposed mechanism is induction of hepatic microsomal enzymes during chronic alcohol use, which may result in accelerated metabolism of acetaminophen and increased production of potentially hepatotoxic metabolites.

Management

In general, chronic alcoholics should avoid regular or excessive use of acetaminophen. Alternative analgesic/antipyretic therapy may be appropriate in patients who consume three or more alcoholic drinks per day.

References (1)
  1. (2022) "Product Information. Acetaminophen (acetaminophen)." Camber Pharmaceuticals, Inc
Major:

dihydrocodeine Food/Lifestyle

Applies to: acetaminophen / caffeine / dihydrocodeine
Generally avoid

Alcohol may potentiate the central nervous system (CNS) depressant effects of opioid analgesics. Concomitant use may result in additive CNS depression and impairment of judgment, thinking, and psychomotor skills. In more severe cases, hypotension, respiratory depression, profound sedation, coma, or even death may occur. In addition, alcohol may affect opioid release from sustained-release formulations.

Management

Patients should not consume alcoholic beverages or use drug products that contain alcohol during treatment with opioid analgesics. Any history of alcohol or illicit drug use should be considered when prescribing an opioid analgesic, and therapy initiated at a lower dosage if necessary. Patients should be closely monitored for signs and symptoms of sedation, respiratory depression, and hypotension.

References (9)
  1. (2024) "Product Information. Levorphanol Tartrate (levorphanol)." Virtus Pharmaceuticals LLC
  2. (2025) "Product Information. Nalbuphine Hydrochloride (nalbuphine)." Hospira Inc
  3. (2024) "Product Information. Remifentanil Hydrochloride (remifentanil)." Fresenius Kabi USA, LLC
  4. (2022) "Product Information. Remifentanil (remifentanil)." Wockhardt UK Ltd
  5. (2024) "Product Information. Cyclizine-Dipipanone (cyclizine-dipipanone)." Advanz Pharma
  6. Cherrier MM, Shen DD, Shireman L, et al. (2021) "Elevated customary alcohol consumption attenuates opioid effects." Pharmacol Biochem Behav, 4, p. 1-27
  7. (2025) "Product Information. Dihydrocodeine (dihydrocodeine)." Ennogen Healthcare International Ltd
  8. (2021) "Product Information. Covonia Dry Cough (pholcodine)." Thornton & Ross Ltd
  9. (2018) "Product Information. TUSCALMAN NIÑOS (noscapina)." DESMA LABORATORIO FARMACEUTICO, S.L.

Moderate food/lifestyle interactions

Moderate:

felbamate Food/Lifestyle

Applies to: felbamate
Generally avoid

Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

Management

Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

References (4)
  1. Warrington SJ, Ankier SI, Turner P (1986) "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology, 15, p. 31-7
  2. Gilman AG, eds., Nies AS, Rall TW, Taylor P (1990) "Goodman and Gilman's the Pharmacological Basis of Therapeutics." New York, NY: Pergamon Press Inc.
  3. (2012) "Product Information. Fycompa (perampanel)." Eisai Inc
  4. (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka America Pharmaceutical, Inc.

Minor food/lifestyle interactions

Minor:

caffeine Food/Lifestyle

Applies to: acetaminophen / caffeine / dihydrocodeine

The effect of grapefruit juice on the pharmacologic activity of caffeine is controversial. One report suggests that grapefruit juice increases the effect of caffeine. The proposed mechanism is inhibition of cytochrome P-450 metabolism of caffeine. However, a well-conducted pharmacokinetic/pharmacodynamic study did not demonstrate this effect. The clinical significance of this potential interaction is unknown.

References (2)
  1. (1995) "Grapefruit juice interactions with drugs." Med Lett Drugs Ther, 37, p. 73-4
  2. Maish WA, Hampton EM, Whitsett TL, Shepard JD, Lovallo WR (1996) "Influence of grapefruit juice on caffeine pharmacokinetics and pharmacodynamics." Pharmacotherapy, 16, p. 1046-52

Disease interactions

63 potential interactions Applies to: 46 conditions, including High Blood Pressure, Depression, GERD, Constipation, and Heart Attack.

Acute Alcohol Intoxication

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Acute Alcohol Intoxication.

The use of opiate agonists is contraindicated in patients with acute alcohol intoxication exhibiting depressed vital signs. The central nervous system depressant effects of opiate agonists may be additive with those of alcohol. Severe respiratory depression and death may occur. Therapy with opiate agonists should be administered cautiously in patients who might be prone to acute alcohol intake.

Adrenal Insufficiency

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Adrenal Insufficiency.

Patients with Addison's disease may have increased risk of respiratory depression and prolonged CNS depression associated with the use of narcotic (opioid) analgesic agents. Conversely, these agents may cause or potentiate adrenal insufficiency. Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with adrenocortical insufficiency. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Alcoholism

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Alcoholism.

Opiate agonists have the potential to cause dependence and abuse. Tolerance as well as physical and psychological dependence can develop after prolonged use. Abrupt cessation, reduction in dosage, or administration of an opiate antagonist such as naloxone may precipitate withdrawal symptoms. In patients who have developed tolerance to an opiate agonist, overdosage can still produce respiratory depression and death, and cross-tolerance usually will occur with other agents in the class. Addiction-prone individuals, such as those with a history of alcohol or substance abuse, should be under careful surveillance or medical supervision when treated with opiate agonists. It may be prudent to refrain from dispensing large quantities of medication to these patients. After prolonged use or if dependency is suspected, withdrawal of opiate therapy should be undertaken gradually using a dosage-tapering schedule.

Major:

acetaminophen / caffeine / dihydrocodeine

The acetaminophen in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Alcoholism.

Chronic alcohol abusers may be at increased risk of hepatotoxicity during treatment with acetaminophen (APAP). Severe liver injury, including cases of acute liver failure resulting in liver transplant and death, has been reported in patients using acetaminophen. Therapy with acetaminophen should be administered cautiously, if at all, in patients who consume three or more alcoholic drinks a day. In general, patients should avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure. They should also be advised to seek medical attention if they experience signs and symptoms of liver injury such as fever, rash, anorexia, nausea, vomiting, fatigue, right upper quadrant pain, dark urine, and jaundice.

Altered Consciousness

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Altered Consciousness.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Anemia

Major:

felbamate

Felbamate has a major potential interaction with Anemia.

The use of felbamate is contraindicated in patients with bone marrow suppression or a current or prior history of blood dyscrasias. A marked increase in the incidence of aplastic anemia has been associated with the use of felbamate, reportedly exceeding 100 times the incidence observed in the general population (2 to 5 per million persons per year). In the few cases that have been reported in felbamate patients, the onset of clinical manifestations of aplastic anemia ranged from 5 to 30 weeks. However, the injury to bone marrow stem cells that is believed to be ultimately responsible for the anemia may occur much earlier. Currently, it is not known whether the risk is related to dose, duration of exposure, and/or concomitant use of other antiepileptic or myelotoxic drugs. Expert hematologic consultation should be available for all patients treated with felbamate. Since aplastic anemia typically develops without premonitory clinical or laboratory signs, it should be borne in mind that routine blood testing may not be reliably used to prevent development of the syndrome. However, in some cases, it may allow the detection of hematologic changes before the condition is full-blown. Felbamate therapy should be withdrawn if evidence of bone marrow depression is observed. Patients who are discontinued from the drug may remain at risk for developing anemia for a variable and unknown period afterwards and should be monitored accordingly.

Angina

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Angina.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

Arrhythmia

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Arrhythmia.

Opiate agonists have cholinergic activity. Large doses and/or rapid intravenous administration may produce bradycardia and arrhythmias via stimulation of medullary vagal nuclei. Therapy with opiate agonists should be administered cautiously in patients with a history of arrhythmias. Clinical monitoring of cardiovascular status is recommended during therapy.

Asphyxia

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Asphyxia.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Biliary Obstruction

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Biliary Obstruction.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Bone Marrow Depression/Low Blood Counts

Major:

felbamate

Felbamate has a major potential interaction with Bone Marrow Depression/Low Blood Counts.

The use of felbamate is contraindicated in patients with bone marrow suppression or a current or prior history of blood dyscrasias. A marked increase in the incidence of aplastic anemia has been associated with the use of felbamate, reportedly exceeding 100 times the incidence observed in the general population (2 to 5 per million persons per year). In the few cases that have been reported in felbamate patients, the onset of clinical manifestations of aplastic anemia ranged from 5 to 30 weeks. However, the injury to bone marrow stem cells that is believed to be ultimately responsible for the anemia may occur much earlier. Currently, it is not known whether the risk is related to dose, duration of exposure, and/or concomitant use of other antiepileptic or myelotoxic drugs. Expert hematologic consultation should be available for all patients treated with felbamate. Since aplastic anemia typically develops without premonitory clinical or laboratory signs, it should be borne in mind that routine blood testing may not be reliably used to prevent development of the syndrome. However, in some cases, it may allow the detection of hematologic changes before the condition is full-blown. Felbamate therapy should be withdrawn if evidence of bone marrow depression is observed. Patients who are discontinued from the drug may remain at risk for developing anemia for a variable and unknown period afterwards and should be monitored accordingly.

Brain Tumor

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Brain Tumor.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Brain Tumor.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Cerebral Vascular Disorder

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Cerebral Vascular Disorder.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Cerebral Vascular Disorder.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Constipation

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Constipation.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Dehydration

Major:

acetaminophen / caffeine / dihydrocodeine

The acetaminophen in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Dehydration.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Dehydration.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Depression

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Depression.

The use of CNS stimulants can cause psychotic symptoms, suicidal ideation, and aggression, and can exacerbate symptoms of behavior disturbance and thought disorder; CNS stimulants may induce a manic or mixed episode in patients with bipolar disorder. Psychiatric symptoms have been reported in patients with and without history of psychiatric disorders. All patients (particularly those with psychotic or bipolar disorders) should be monitored closely, especially during treatment initiation and at times of dose changes. Extreme caution should be exercised when CNS stimulants are given to patients with a history of psychosis, depression, mania, or bipolar disorder. Prior to initiating therapy, all patients should be screened for risk factors for developing a manic episode (e.g., comorbid or history of depressive symptoms or family history of suicide, bipolar disease, or depression). If any psychiatric symptoms emerge or are exacerbated, treatment suspension should be considered. Some CNS stimulants are contraindicated in patients with marked agitation or anxiety.

Moderate:

felbamate

Felbamate has a moderate potential interaction with Depression.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Drug Dependence

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Drug Dependence.

Opiate agonists have the potential to cause dependence and abuse. Tolerance as well as physical and psychological dependence can develop after prolonged use. Abrupt cessation, reduction in dosage, or administration of an opiate antagonist such as naloxone may precipitate withdrawal symptoms. In patients who have developed tolerance to an opiate agonist, overdosage can still produce respiratory depression and death, and cross-tolerance usually will occur with other agents in the class. Addiction-prone individuals, such as those with a history of alcohol or substance abuse, should be under careful surveillance or medical supervision when treated with opiate agonists. It may be prudent to refrain from dispensing large quantities of medication to these patients. After prolonged use or if dependency is suspected, withdrawal of opiate therapy should be undertaken gradually using a dosage-tapering schedule.

Gallbladder Disease

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Gallbladder Disease.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Gastrointestinal Obstruction

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Gastrointestinal Obstruction.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Gastrointestinal Obstruction.

Opioid analgesics are contraindicated in patients with known or suspected gastrointestinal obstruction, including paralytic ileus.

GERD

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with GERD.

Methylxanthines increase gastric acidity and may also relax lower esophageal sphincter, which can lead to gastric reflux into the esophagus. Therapy with products containing methylxanthines should be administered cautiously in patients with significant gastroesophageal reflux.

Head Injury

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Head Injury.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Head Injury.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Heart Attack

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Heart Attack.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

Heart Disease

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Heart Disease.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

High Blood Pressure

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with High Blood Pressure.

CNS stimulants increase blood pressure and heart rate; the use of some agents may be contraindicated in patients with severe/uncontrolled hypertension. Caution should be used when administering to patients with preexisting high blood pressure (even mild hypertension) and other cardiovascular conditions. All patients under treatment should be regularly monitored for potential tachycardia and hypertension.

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with High Blood Pressure.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with High Blood Pressure.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

History of Blood Dyscrasias

Major:

felbamate

Felbamate has a major potential interaction with History of Blood Dyscrasias.

The use of felbamate is contraindicated in patients with bone marrow suppression or a current or prior history of blood dyscrasias. A marked increase in the incidence of aplastic anemia has been associated with the use of felbamate, reportedly exceeding 100 times the incidence observed in the general population (2 to 5 per million persons per year). In the few cases that have been reported in felbamate patients, the onset of clinical manifestations of aplastic anemia ranged from 5 to 30 weeks. However, the injury to bone marrow stem cells that is believed to be ultimately responsible for the anemia may occur much earlier. Currently, it is not known whether the risk is related to dose, duration of exposure, and/or concomitant use of other antiepileptic or myelotoxic drugs. Expert hematologic consultation should be available for all patients treated with felbamate. Since aplastic anemia typically develops without premonitory clinical or laboratory signs, it should be borne in mind that routine blood testing may not be reliably used to prevent development of the syndrome. However, in some cases, it may allow the detection of hematologic changes before the condition is full-blown. Felbamate therapy should be withdrawn if evidence of bone marrow depression is observed. Patients who are discontinued from the drug may remain at risk for developing anemia for a variable and unknown period afterwards and should be monitored accordingly.

Hyperthyroidism

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Hyperthyroidism.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Hyperthyroidism.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

Hypotension

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Hypotension.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Infectious Gastroenteritis

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Infectious Gastroenteritis.

Narcotic (opioid) analgesic agents may prolong and/or worsen diarrhea associated with organisms that invade the intestinal mucosa, such as toxigenic Escherichia coli, Salmonella, Shigella, and pseudomembranous colitis due to broad-spectrum antibiotics. These agents decrease gastrointestinal motility, which may delay the excretion of infective gastroenteric organisms and/or their toxins. Other symptoms and complications such as fever, shedding of organisms, and extraintestinal illness may also be increased or prolonged. Therapy with opioids should be avoided or administered cautiously in patients with infectious diarrhea, particularly that due to pseudomembranous enterocolitis or enterotoxin-producing bacteria or if accompanied by high fever, pus, or blood in the stool.

Inflammatory Bowel Disease

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Inflammatory Bowel Disease.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Intestinal Anastomoses

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Intestinal Anastomoses.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Liver Disease

Major:

acetaminophen / caffeine / dihydrocodeine

The acetaminophen in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Liver Disease.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Major:

felbamate

Felbamate has a major potential interaction with Liver Disease.

The use of felbamate is contraindicated in patients with a history of hepatic impairment. A marked increase in the incidence of hepatic failure, some resulting in fatality, has been associated with the use of felbamate relative to that expected in the general population (approximately 2000 cases per year). Currently, it is not known whether the risk is related to dose, duration of exposure, and/or concomitant use of other antiepileptic or hepatotoxic drugs. All patients treated with felbamate should have serum transaminase and bilirubin levels checked prior to initiating therapy and at 1- to 2-week intervals while treatment continues. Felbamate therapy should be withdrawn if abnormal liver function tests occur.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Liver Disease.

In general, CNS stimulants are extensively metabolized by the liver. Their plasma clearance may be decreased and their half-life prolonged in patients with impaired hepatic function. Therapy with CNS stimulants should be administered cautiously in patients with moderate to severe liver disease, and the dosage should be adjusted accordingly in certain agents. Additionally, postmarketing reports have shown that atomoxetine can cause severe liver injury; laboratory testing should be done at the first sign/symptom of liver dysfunction (jaundice, dark urine, upper quadrant tenderness) and treatment should be discontinued in patients with evidence of liver injury.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Liver Disease.

Narcotic (opioid) analgesic agents are extensively metabolized by the liver, and several of them (e.g., codeine, hydrocodone, meperidine, methadone, morphine, propoxyphene) have active metabolites that are further converted to inactive substances. The serum concentrations of these agents and their metabolites may be increased and the half-lives prolonged in patients with impaired hepatic function. Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with liver disease. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Malnourishment

Major:

acetaminophen / caffeine / dihydrocodeine

The acetaminophen in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Malnourishment.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Pancreatitis

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Pancreatitis.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Peptic Ulcer

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Peptic Ulcer.

Methylxanthines are known to stimulate peptic acid secretion. Therapy with products containing methylxanthines should be administered with extreme caution in patients with active peptic ulcer disease. Some manufacturers consider their use to be contraindicated under such circumstance.

Peripheral Arterial Disease

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Peripheral Arterial Disease.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Phenylketonuria

Moderate:

acetaminophen / caffeine / dihydrocodeine

The acetaminophen in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Phenylketonuria.

Several oral acetaminophen and acetaminophen-combination products, particularly flavored chewable tablets, contain the artificial sweetener, aspartame (NutraSweet). Aspartame is converted to phenylalanine in the gastrointestinal tract following ingestion. Chewable and effervescent formulations of acetaminophen products may also contain phenylalanine. The aspartame/phenylalanine content should be considered when these products are used in patients who must restrict their intake of phenylalanine (i.e. phenylketonurics).

Pheochromocytoma

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Pheochromocytoma.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Post MI Syndrome

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Post MI Syndrome.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

Prematurity/Underweight in Infancy

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Prematurity/Underweight in Infancy.

The use of narcotic (opioid) analgesic agents is contraindicated in premature infants. These agents may cross the immature blood-brain barrier to a greater extent than in adults, resulting in disproportionate respiratory depression.

Psychosis

Major:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Psychosis.

The use of CNS stimulants can cause psychotic symptoms, suicidal ideation, and aggression, and can exacerbate symptoms of behavior disturbance and thought disorder; CNS stimulants may induce a manic or mixed episode in patients with bipolar disorder. Psychiatric symptoms have been reported in patients with and without history of psychiatric disorders. All patients (particularly those with psychotic or bipolar disorders) should be monitored closely, especially during treatment initiation and at times of dose changes. Extreme caution should be exercised when CNS stimulants are given to patients with a history of psychosis, depression, mania, or bipolar disorder. Prior to initiating therapy, all patients should be screened for risk factors for developing a manic episode (e.g., comorbid or history of depressive symptoms or family history of suicide, bipolar disease, or depression). If any psychiatric symptoms emerge or are exacerbated, treatment suspension should be considered. Some CNS stimulants are contraindicated in patients with marked agitation or anxiety.

Moderate:

felbamate

Felbamate has a moderate potential interaction with Psychosis.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Pulmonary Impairment

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Pulmonary Impairment.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Renal Dysfunction

Major:

felbamate

Felbamate has a major potential interaction with Renal Dysfunction.

Felbamate is partially eliminated by the kidney as unchanged drug (approximately 40% to 50% of absorbed dose). The plasma clearance of felbamate may be decreased and the half-life prolonged in patients with impaired renal function. Therapy with felbamate should be administered cautiously in patients with renal impairment.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Renal Dysfunction.

Although narcotic (opioid) analgesic agents are generally metabolized by the liver, renal impairment can alter the elimination of these agents and their metabolites (some of which are pharmacologically active), resulting in drug accumulation and increased risk of toxicity. Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with significantly impaired renal function. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Renal Dysfunction.

Overall CNS stimulants should be administered with caution in patients with significantly impaired renal function as the reduction in the rate of elimination may alter the therapeutic response. The dosage should be adjusted accordingly in certain agents.

Respiratory Arrest

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Respiratory Arrest.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Seizures

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Seizures.

Narcotic (opioid) analgesic agents may increase the frequency of seizures in patients with seizure disorders, may increase the risk of seizures occurring in other clinical settings associated with seizures, and, at higher dosages, have been reported to induce seizures in patients without history of seizures. Patients with history of seizure disorders should be regularly evaluated for worsened seizure control during therapy. Prolonged meperidine use may increase the risk of toxicity (e.g., seizures) from the accumulation of the active metabolite (normeperidine).

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Seizures.

Due to general central nervous system stimulation, therapy with CNS stimulant drugs may cause seizures. These drugs may lower the convulsive threshold in patients with history of seizures, with prior electroencephalogram (EEG) abnormalities without seizures, and very rarely, without history of seizures and no prior EEG evidence of seizures. Therapy with CNS stimulants should be used with caution in patients with or predisposed to seizures. If seizures occur, therapy should be discontinued.

Shock

Major:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a major potential interaction with Shock.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Tachyarrhythmia

Moderate:

acetaminophen / caffeine / dihydrocodeine

The caffeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Tachyarrhythmia.

Like other methylxanthines, caffeine at high dosages may be associated with positive inotropic and chronotropic effects on the heart. Caffeine may also produce an increase in systemic vascular resistance, resulting in elevation of blood pressure. Therapy with products containing caffeine should be administered cautiously in patients with severe cardiac disease, hypertension, hyperthyroidism, or acute myocardial injury. Some clinicians recommend avoiding caffeine in patients with symptomatic cardiac arrhythmias and/or palpitations and during the first several days to weeks after an acute myocardial infarction.

Urinary Retention

Moderate:

acetaminophen / caffeine / dihydrocodeine

The dihydrocodeine in acetaminophen / caffeine / dihydrocodeine has a moderate potential interaction with Urinary Retention.

Narcotic (opioid) analgesic agents may inhibit the urinary voiding reflex and increase the tone of the vesical sphincter in the bladder. Acute urinary retention requiring catheterization may occur, particularly in patients with prostatic hypertrophy or urethral stricture and in older adult patients. These agents may also decrease urine production via direct effects on the kidney and central stimulation of the release of vasopressin. Therapy with opioids should be administered cautiously in patients with or predisposed to urinary retention and/or oliguria. The effects on smooth muscle tone appear to be the most pronounced with morphine.

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acetaminophen / caffeine / dihydrocodeine

A total of 1015 drugs are known to interact with acetaminophen / caffeine / dihydrocodeine.

felbamate

A total of 553 drugs are known to interact with felbamate.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.