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Drug Interactions between Re-Drylex Jr and timolol

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

timolol phenylephrine

Applies to: timolol and Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

MONITOR: A case report suggests that beta-blockers may enhance the pressor response to phenylephrine. The proposed mechanism involves blockade of beta-2 adrenergic receptors in the peripheral vasculature, resulting in unopposed alpha-adrenergic effect of phenylephrine that is responsible for vasoconstriction. Additionally, beta-blockers may desensitize baroreceptors that normally modulate heart rate in response to blood pressure elevations by increasing vagal activity on the sinoauricular node. In the case report, a woman with a history of hypertension treated with hydrochlorothiazide (50 mg twice a day) and propranolol (40 mg four times a day) developed sudden bitemporal pain and became unconscious shortly after she was given one drop of a 10% phenylephrine solution in each eye during an ophthalmic examination. She subsequently died of intracerebral hemorrhage due to rupture of a berry aneurysm. The authors noted that the patient had received the same eye drop without incident on two previous occasions when she was not receiving blood pressure or other medications. Nevertheless, an interaction between phenylephrine and beta-blockers is not well established. Phenylephrine acts predominantly on alpha-adrenergic receptors and has little or no direct effect on beta-2 adrenergic receptors, although it may affect them indirectly by enhancing release of norepinephrine from adrenergic nerve terminals. In a study of 12 patients with hypertension, mean phenylephrine doses required to increase systolic blood pressure by 25 mmHg were not significantly different following 2 weeks on propranolol, metoprolol, and placebo (4.8 mcg/kg, 4.7 mcg/kg, and 5.3 mcg/kg, respectively). Baroreceptor-mediated decreases in heart rate during phenylephrine infusion were also in the same range on propranolol, metoprolol, and placebo over baseline heart rate values. In another study, no changes in blood pressure or heart rate were observed in hypertensive patients treated with metoprolol who were given 0.5 to 4 mg doses of phenylephrine intranasally every hour up to a total of 7.5 to 15 mg, or 4 to 30 times the usual recommended dose, compared to placebo or baseline values. These results support the lack of a significant interaction between beta-blockers and phenylephrine.

MANAGEMENT: Until more information is available, caution should be exercised when phenylephrine is used in combination with beta-blockers including ophthalmic formulations, which may be systemically absorbed and can produce clinically significant systemic effects even at low or undetectable plasma levels. Monitoring of blood pressure should be considered, particularly when phenylephrine is administered intravenously or intraocularly. Although an interaction is not likely to occur with cardioselective beta-blockers, caution may be advisable when high dosages are used, since cardioselectivity is not absolute and may be lost with larger doses. A beta-blocker such as propranolol may be used to treat cardiac arrhythmias that occur during administration of phenylephrine.

References

  1. Cass E, Kadar D, Stein HA (1979) "Hazards of phenylephrine topical medication in persons taking propranolol." Can Med Assoc J, 120, p. 1261-2
  2. Myers MG, Iazzetta JJ (1982) "Intranasally administered phenylephrine and blood pressure." Can Med Assoc J, 127, p. 365-6

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Moderate

timolol methscopolamine

Applies to: timolol and Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

MONITOR: Anticholinergic agents frequently cause drowsiness and other central nervous system-depressant effects that may be additive with those induced by beta blockers. In addition, these agents may increase heart rate and theoretically may counteract the bradycardic effects of beta blockers. Pharmacokinetically, anticholinergic agents may delay the gastrointestinal absorption of beta blockers and other drugs that are administered orally. The proposed mechanism involves increased gastrointestinal transit time due to reduction of stomach and intestinal motility by anticholinergic agents. In healthy volunteers, pretreatment with propantheline has been shown to prolong the time to reach peak plasma concentration (Tmax) for both atenolol and metoprolol. Propantheline also decreased metoprolol peak plasma concentration (Cmax) but had no effect on its systemic exposure (AUC). In contrast, propantheline increased atenolol AUC but had no effect on its Cmax. The clinical relevance of these changes is probably minimal.

MANAGEMENT: Clinicians should be aware of the potential for diminished effects of beta blockers during coadministration with anticholinergic agents. Patients should also be monitored for potentially excessive CNS adverse effects (e.g., drowsiness, dizziness, lightheadedness, confusion, blurred vision) if these agents are used in combination. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.

References

  1. Briant RH, Dorrington RE, Ferry DG, Paxton JW (1983) "Bioavailability of metoprolol in young adults and the elderly, with additional studies on the effects of metoclopramide and probanthine." Eur J Clin Pharmacol, 25, p. 353-6
  2. Clark JM, Seager SJ (1983) "Gastric emptying following premedication with glycopyrrolate or atropine." Br J Anaesth, 55, p. 1195-9
  3. Regardh CG, Lundborg P, Persson BA (1981) "The effect of antacid, metoclopramide, and propantheline on the bioavailability of metoprolol and atenolol." Biopharm Drug Dispos, 2, p. 79-87
  4. 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.
  5. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  6. Cerner Multum, Inc. "Australian Product Information."
View all 6 references

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Moderate

chlorpheniramine methscopolamine

Applies to: Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine) and Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

MONITOR: Agents with anticholinergic properties (e.g., sedating antihistamines; antispasmodics; neuroleptics; phenothiazines; skeletal muscle relaxants; tricyclic antidepressants; disopyramide) may have additive effects when used in combination. Excessive parasympatholytic effects may result in paralytic ileus, hyperthermia, heat stroke, and the anticholinergic intoxication syndrome. Peripheral symptoms of intoxication commonly include mydriasis, blurred vision, flushed face, fever, dry skin and mucous membranes, tachycardia, urinary retention, and constipation. Central symptoms may include memory loss, disorientation, incoherence, hallucinations, psychosis, delirium, hyperactivity, twitching or jerking movements, stereotypy, and seizures. Central nervous system-depressant effects may also be additively or synergistically increased when these agents are combined, especially in elderly or debilitated patients. Use of neuroleptics in combination with other neuroleptics or anticholinergic agents may increase the risk of tardive dyskinesia. In addition, some neuroleptics and tricyclic antidepressants may cause prolongation of the QT interval and theoretically, concurrent use of two or more drugs that can cause QT interval prolongation may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death.

MANAGEMENT: Caution is advised when agents with anticholinergic properties are combined, particularly in the elderly and those with underlying organic brain disease, who tend to be more sensitive to the central anticholinergic effects of these drugs and in whom toxicity symptoms may be easily overlooked. Patients should be advised to notify their physician promptly if they experience potential symptoms of anticholinergic intoxication such as abdominal pain, fever, heat intolerance, blurred vision, confusion, and/or hallucinations. Ambulatory patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them. A reduction in anticholinergic dosages may be necessary if excessive adverse effects develop.

References

  1. Stadnyk AN, Glezos JD (1983) "Drug-induced heat stroke." Can Med Assoc J, 128, p. 957-9
  2. Zelman S, Guillan R (1970) "Heat stroke in phenothiazine-treated patients: a report of three fatalities." Am J Psychiatry, 126, p. 1787-90
  3. Mann SC, Boger WP (1978) "Psychotropic drugs, summer heat and humidity, and hyperplexia: a danger restated." Am J Psychiatry, 135, p. 1097-100
  4. Warnes H, Lehmann HE, Ban TA (1967) "Adynamic ileus during psychoactive medication: a report of three fatal and five severe cases." Can Med Assoc J, 96, p. 1112-3
  5. Gershon S, Neubauer H, Sundland DM (1965) "Interaction between some anticholinergic agents and phenothiazines." Clin Pharmacol Ther, 6, p. 749-56
  6. Sarnquist F, Larson CP Jr (1973) "Drug-induced heat stroke." Anesthesiology, 39, p. 348-50
  7. Johnson AL, Hollister LE, Berger PA (1981) "The anticholinergic intoxication syndrome: diagnosis and treatment." J Clin Psychiatry, 42, p. 313-7
  8. Lee BS (1986) "Possibility of hyperpyrexia with antipsychotic and anticholinergic drugs." J Clin Psychiatry, 47, p. 571
  9. Forester D (1978) "Fatal drug-induced heat stroke." JACEP, 7, p. 243-4
  10. Moreau A, Jones BD, Banno V (1986) "Chronic central anticholinergic toxicity in manic depressive illness mimicking dementia." Can J Psychiatry, 31, p. 339-41
  11. Hvizdos AJ, Bennett JA, Wells BG, Rappaport KB, Mendel SA (1983) "Anticholinergic psychosis in a patient receiving usual doses of haloperidol." Clin Pharm, 2, p. 174-8
  12. Cohen MA, Alfonso CA, Mosquera M (1994) "Development of urinary retention during treatment with clozapine and meclizine [published erratum appears in Am J Psychiatry 1994 Jun;151(6):952]." Am J Psychiatry, 151, p. 619-20
  13. (2001) "Product Information. Cogentin (benztropine)." Merck & Co., Inc
  14. Kulik AV, Wilbur R (1982) "Delirium and stereotypy from anticholinergic antiparkinson drugs." Prog Neuropsychopharmacol Biol Psychiatry, 6, p. 75-82
  15. (2001) "Product Information. Artane (trihexyphenidyl)." Lederle Laboratories
View all 15 references

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Moderate

phenylephrine methscopolamine

Applies to: Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine) and Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

MONITOR: The pressor response to phenylephrine may be potentiated by the vagolytic effect of atropine, which inhibits the reflex bradycardia that would normally accompany any increases in blood pressure induced by phenylephrine. Other antimuscarinic agents may also participate in this interaction, although clinical data are lacking. In one report, pseudo-pheochromocytoma (i.e., significant increases in blood pressure and tachycardia) occurred in seven patients who underwent eye surgery and were given phenylephrine 10% ophthalmic solution and systemic atropine, three of whom subsequently developed left ventricular failure and pulmonary edema that required intensive care monitoring. Two patients had preexisting hypertension, while others had no known history of cardiovascular disease. All had received general anesthesia with propofol, phenoperidine, and vecuronium. Since phenylephrine use alone may be associated with cardiovascular toxicities including hypertension, arrhythmia, myocardial infarction and cardiac failure, the extent of involvement by atropine is uncertain. The authors reported no further cardiovascular events following implementation of various measures that reduced phenylephrine dosage and systemic exposure, including: use of a milder strength of phenylephrine ophthalmic solution; swabbing to minimize drainage into the nasolachrymal duct to the nasal mucosa; and use of a cannula to reduce drop size. In a study of six healthy volunteers, diastolic and systolic blood pressure increased by 4 mmHg following administration of phenylephrine (0.42 mcg/kg/min), compared to 17 mmHg when phenylephrine was given after three doses of atropine (0.02, 0.01 and 0.01 mg/kg at 30 minute intervals).

MANAGEMENT: Caution is advised if phenylephrine (systemic or ophthalmic) is used in combination with atropine or other antimuscarinic agents. Cardiovascular status, including blood pressure and heart rate, should be closely monitored. When using ophthalmic formulations, measures to minimize systemic absorption should be employed, such as digital compression of the lacrimal sac or lid closure after instillation. A milder strength (< 10%) is preferable if phenylephrine ophthalmic solution is given.

References

  1. Daelman F, Andrejak M, Rajaonarivony D, Bryselbout E, Jezraoui P, Ossart M (1994) "Phenylephrine eyedrops, systemic atropine and cardiovascular adverse events." Therapie, 49, p. 467
  2. Fraunfelder FT, Fraunfelder FW; Randall JA (2001) "Drug-Induced Ocular Side Effects" Boston, MA: Butterworth-Heinemann
  3. Lai YK (1989) "Adverse effect of intraoperative phenylephrine 10%: case report." Br J Ophthalmol, 73, p. 468-9
  4. Van Der Spek AF, Hantler CB (1986) "Phenylephrine eyedrops and anesthesia." Anesthesiology, 64, p. 812-4
  5. Levine MA, Leenen FH (1992) "Role of vagal activity in the cardiovascular responses to phenylephrine in man." Br J Clin Pharmacol, 33, p. 333-6
View all 5 references

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Drug and food interactions

Moderate

chlorpheniramine food

Applies to: Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

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

  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 American Pharmaceuticals Inc
View all 4 references

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Moderate

timolol food

Applies to: timolol

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

References

  1. Sternbach H (1991) "Fluoxetine-associated potentiation of calcium-channel blockers." J Clin Psychopharmacol, 11, p. 390-1
  2. Shook TL, Kirshenbaum JM, Hundley RF, Shorey JM, Lamas GA (1984) "Ethanol intoxication complicating intravenous nitroglycerin therapy." Ann Intern Med, 101, p. 498-9
  3. Feder R (1991) "Bradycardia and syncope induced by fluoxetine." J Clin Psychiatry, 52, p. 139
  4. Ellison JM, Milofsky JE, Ely E (1990) "Fluoxetine-induced bradycardia and syncope in two patients." J Clin Psychiatry, 51, p. 385-6
  5. Rodriguez de la Torre B, Dreher J, Malevany I, et al. (2001) "Serum levels and cardiovascular effects of tricyclic antidepressants and selective serotonin reuptake inhibitors in depressed patients." Ther Drug Monit, 23, p. 435-40
  6. Cerner Multum, Inc. "Australian Product Information."
  7. Pacher P, Kecskemeti V (2004) "Cardiovascular side effects of new antidepressants and antipsychotics: new drugs, old concerns?" Curr Pharm Des, 10, p. 2463-75
  8. Andrews C, Pinner G (1998) "Postural hypotension induced by paroxetine." BMJ, 316, p. 595
View all 8 references

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Moderate

methscopolamine food

Applies to: Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

GENERALLY AVOID: Use of anticholinergic agents with alcohol may result in sufficient impairment of attention so as to render driving and operating machinery more hazardous. In addition, the potential for abuse may be increased with the combination. The mechanism of interaction is not established but may involve additive depressant effects on the central nervous system. No effect of oral propantheline or atropine on blood alcohol levels was observed in healthy volunteers when administered before ingestion of a standard ethanol load. However, one study found impairment of attention in subjects given atropine 0.5 mg or glycopyrrolate 1 mg in combination with alcohol.

MANAGEMENT: Alcohol should generally be avoided during therapy with anticholinergic agents. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.

References

  1. Linnoila M (1973) "Drug effects on psychomotor skills related to driving: interaction of atropine, glycopyrrhonium and alcohol." Eur J Clin Pharmacol, 6, p. 107-12

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Moderate

timolol food

Applies to: timolol

ADJUST DOSING INTERVAL: Concurrent administration with calcium salts may decrease the oral bioavailability of atenolol and possibly other beta-blockers. The exact mechanism of interaction is unknown. In six healthy subjects, calcium 500 mg (as lactate, carbonate, and gluconate) reduced the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of atenolol (100 mg) by 51% and 32%, respectively. The elimination half-life increased by 44%. Twelve hours after the combination, beta-blocking activity (as indicated by inhibition of exercise tachycardia) was reduced compared to that with atenolol alone. However, during a 4-week treatment in six hypertensive patients, there was no difference in blood pressure values between treatments. The investigators suggest that prolongation of the elimination half-life induced by calcium coadministration may have led to atenolol cumulation during long-term dosing, which compensated for the reduced bioavailability.

MANAGEMENT: It may help to separate the administration times of beta-blockers and calcium products by at least 2 hours. Patients should be monitored for potentially diminished beta-blocking effects following the addition of calcium therapy.

References

  1. Kirch W, Schafer-Korting M, Axthelm T, Kohler H, Mutschler E (1981) "Interaction of atenolol with furosemide and calcium and aluminum salts." Clin Pharmacol Ther, 30, p. 429-35

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Moderate

phenylephrine food

Applies to: Re-Drylex Jr (chlorpheniramine / methscopolamine / phenylephrine)

MONITOR: Coadministration of two or more sympathomimetic agents may increase the risk of adverse effects such as nervousness, irritability, and increased heart rate. Central nervous system (CNS) stimulants, particularly amphetamines, can potentiate the adrenergic response to vasopressors and other sympathomimetic agents. Additive increases in blood pressure and heart rate may occur due to enhanced peripheral sympathetic activity.

MANAGEMENT: Caution is advised if two or more sympathomimetic agents are coadministered. Pulse and blood pressure should be closely monitored.

References

  1. Rosenblatt JE, Lake CR, van Kammen DP, Ziegler MG, Bunney WE Jr (1979) "Interactions of amphetamine, pimozide, and lithium on plasma norepineophrine and dopamine-beta-hydroxylase in schizophrenic patients." Psychiatry Res, 1, p. 45-52
  2. Cavanaugh JH, Griffith JD, Oates JA (1970) "Effect of amphetamine on the pressor response to tyramine: formation of p-hydroxynorephedrine from amphetamine in man." Clin Pharmacol Ther, 11, p. 656
  3. (2001) "Product Information. Adderall (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc
  4. (2001) "Product Information. Tenuate (diethylpropion)." Aventis Pharmaceuticals
  5. (2001) "Product Information. Sanorex (mazindol)." Novartis Pharmaceuticals
  6. (2001) "Product Information. Focalin (dexmethylphenidate)." Mikart Inc
  7. (2002) "Product Information. Strattera (atomoxetine)." Lilly, Eli and Company
View all 7 references

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.


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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.