Drug Interactions between clozapine and Limbitrol DS
This report displays the potential drug interactions for the following 2 drugs:
- clozapine
- Limbitrol DS (amitriptyline/chlordiazepoxide)
Interactions between your drugs
amitriptyline cloZAPine
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide) and clozapine
MONITOR CLOSELY: Coadministration with other psychotropic agents may potentiate the adverse effects of clozapine on cardiovascular function. Orthostatic hypotension with or without syncope, in rare cases accompanied by profound collapse and cardiorespiratory arrest, has occurred during initiation of clozapine treatment alone and in combination with other psychotropic agents, occasionally even on the first dose. The risk is greatest during initial titration in association with rapid dose escalation. In one report, initial doses as low as 12.5 mg were associated with collapse and respiratory arrest. Other adverse effects that may be increased during use of clozapine with other psychotropic agents include CNS depression, tardive dyskinesia, blood dyscrasias (leukopenia, neutropenia, agranulocytosis), tachycardia, and ECG changes such as QT interval prolongation. Anticholinergic effects of these agents may also be additively increased. Excessive anticholinergic effects may result in paralytic ileus, hyperthermia, heat stroke, and the anticholinergic intoxication syndrome. Peripheral symptoms of anticholinergic 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.
MANAGEMENT: Caution is advised when clozapine is initiated in patients receiving other psychotropic drugs. Vital signs should be closely monitored. Patients who have had even a brief interval off clozapine (i.e. 2 or more days since the last dose) should be restarted with 12.5 mg once or twice daily. The potential for additive effects on the QT interval and increased risk of torsade de pointes arrhythmia should also be considered when clozapine is used in combination with phenothiazines, tricyclic antidepressants, some atypical antipsychotics (e.g., asenapine, quetiapine, iloperidone, iloperidone, paliperidone, risperidone, ziprasidone), or other psychotherapeutic agents that can prolong the QT interval such as amoxapine, haloperidol, maprotiline, mirtazapine, and trazodone. Serum electrolytes, including potassium, magnesium and calcium, should be measured at baseline and periodically during treatment, and any abnormalities corrected prior to initiating clozapine. Routine ECG assessment may detect QTc prolongation but is not always effective in preventing arrhythmias. Clozapine treatment should be discontinued if the QTc interval exceeds 500 msec. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope. Ambulatory patients may want to avoid activities requiring mental alertness until they know how these agents affect them. A dosage reduction in one or both drugs may be necessary if excessive adverse effects develop.
References (8)
- Zelman S, Guillan R (1970) "Heat stroke in phenothiazine-treated patients: a report of three fatalities." Am J Psychiatry, 126, p. 1787-90
- Mann SC, Boger WP (1978) "Psychotropic drugs, summer heat and humidity, and hyperplexia: a danger restated." Am J Psychiatry, 135, p. 1097-100
- 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
- (2001) "Product Information. Clozaril (clozapine)." Novartis Pharmaceuticals
- Johnson AL, Hollister LE, Berger PA (1981) "The anticholinergic intoxication syndrome: diagnosis and treatment." J Clin Psychiatry, 42, p. 313-7
- Moreau A, Jones BD, Banno V (1986) "Chronic central anticholinergic toxicity in manic depressive illness mimicking dementia." Can J Psychiatry, 31, p. 339-41
- 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
- Sala M, Vicentini A, Brambilla P, et al. (2005) "QT interval prolongation related to psychoactive drug treatment: a comparison of monotherapy versus polytherapy." Ann Gen Psychiatry, 4, p. 1
chlordiazePOXIDE cloZAPine
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide) and clozapine
MONITOR CLOSELY: Benzodiazepines and clozapine may have additive effects on respiratory and cardiovascular function. Ataxia, excessive salivation, hypotension, collapse, respiratory depression, respiratory arrest, loss of consciousness, cardiac arrest, and sudden death have been reported. The mechanism is unknown and causality has not been clearly determined.
MANAGEMENT: Caution is advised if concurrent therapy is necessary. Vital signs should be closely monitored.
References (3)
- Cobb CD, Anderson CB, Seidel DR (1991) "Possible interaction between clozapine and lorazepam." Am J Psychiatry, 148, p. 1606-7
- Grohmann R, Ruther E, Sassim N, Schmidt LG (1989) "Adverse effects of clozapine." Psychopharmacology (Berl), 99, s101-4
- Klimke A, Klieser E (1994) "Sudden death after intravenous application of lorazepam in a patient treated with clozapine." Am J Psychiatry, 151, p. 780
amitriptyline chlordiazePOXIDE
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide) and Limbitrol DS (amitriptyline / chlordiazepoxide)
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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- Sotaniemi EA, Anttila M, Rautio A, et al. (1981) "Propranolol and sotalol metabolism after a drinking party." Clin Pharmacol Ther, 29, p. 705-10
- 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
- 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
- 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
- Divoll M, Greenblatt DJ, Lacasse Y, Shader RI (1981) "Benzodiazepine overdosage: plasma concentrations and clinical outcome." Psychopharmacology (Berl), 73, p. 381-3
- Naylor GJ, McHarg A (1977) "Profound hypothermia on combined lithium carbonate and diazepam treatment." Br Med J, 2, p. 22
- Stovner J, Endresen R (1965) "Intravenous anaesthesia with diazepam." Acta Anaesthesiol Scand, 24, p. 223-7
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- Feldman SA, Crawley BE (1970) "Interaction of diazepam with the muscle-relaxant drugs." Br Med J, 1, p. 336-8
- Ochs HR, Greenblatt DJ, Verburg-Ochs B (1984) "Propranolol interactions with diazepam, lorazepam and alprazolam." Clin Pharmacol Ther, 36, p. 451-5
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Drug and food interactions
chlordiazePOXIDE food
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide)
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)
- Warrington SJ, Ankier SI, Turner P (1986) "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology, 15, p. 31-7
- 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.
- (2012) "Product Information. Fycompa (perampanel)." Eisai Inc
- (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc
cloZAPine food
Applies to: clozapine
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)
- Warrington SJ, Ankier SI, Turner P (1986) "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology, 15, p. 31-7
- 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.
- (2012) "Product Information. Fycompa (perampanel)." Eisai Inc
- (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc
amitriptyline food
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide)
GENERALLY AVOID: Concomitant use of ethanol and a tricyclic antidepressant (TCA) may result altered TCA plasma levels and efficacy, and additive impairment of motor skills, especially driving skills. Acute ethanol ingestion may inhibit TCA metabolism, while chronic ingestion of large amounts of ethanol may induce hepatic TCA metabolism.
MANAGEMENT: Patients should be advised to avoid alcohol during TCA therapy. Alcoholics who have undergone detoxification should be monitored for decreased TCA efficacy. Dosage adjustments may be required.
References (7)
- Dorian P, Sellers EM, Reed KL, et al. (1983) "Amitriptyline and ethanol: pharmacokinetic and pharmacodynamic interaction." Eur J Clin Pharmacol, 25, p. 325-31
- Warrington SJ, Ankier SI, Turner P (1986) "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology, 15, p. 31-7
- Sandoz M, Vandel S, Vandel B, Bonin B, Allers G, Volmat R (1983) "Biotransformation of amitriptyline in alcoholic depressive patients." Eur J Clin Pharmacol, 24, p. 615-21
- Ciraulo DA, Barnhill JG, Jaffe JH (1988) "Clinical pharmacokinetics of imipramine and desipramine in alcoholics and normal volunteers." Clin Pharmacol Ther, 43, p. 509-18
- Seppala T, Linnoila M, Elonen E, Mattila MJ, Makl M (1975) "Effect of tricyclic antidepressants and alcohol on psychomotor skills related to driving." Clin Pharmacol Ther, 17, p. 515-22
- Ciraulo DA, Barnhill JG, Jaffe JH, Ciraulo AM, Tarmey MF (1990) "Intravenous pharmacokinetics of 2-hydroxyimipramine in alcoholics and normal controls." J Stud Alcohol, 51, p. 366-72
- Ciraulo DA, Alderson LM, Chapron DJ, Jaffe JH, Subbarao B, Kramer PA (1982) "Imipramine disposition in alcoholics." J Clin Psychopharmacol, 2, p. 2-7
amitriptyline food
Applies to: Limbitrol DS (amitriptyline / chlordiazepoxide)
MONITOR: Smoking cessation may lead to elevated plasma concentrations and enhanced pharmacologic effects of drugs that are substrates of CYP450 1A2 (and possibly CYP450 1A1) and/or certain drugs with a narrow therapeutic index (e.g., flecainide, pentazocine). One proposed mechanism is related to the loss of CYP450 1A2 and 1A1 induction by polycyclic aromatic hydrocarbons in tobacco smoke; when smoking cessation agents are initiated and smoking stops, the metabolism of certain drugs may decrease leading to increased plasma concentrations. The mechanism by which smoking cessation affects narrow therapeutic index drugs that are not known substrates of CYP450 1A2 or 1A1 is unknown. The clinical significance of this interaction is unknown as clinical data are lacking.
MANAGEMENT: Until more information is available, caution is advisable if smoking cessation agents are used concomitantly with drugs that are substrates of CYP450 1A2 or 1A1 and/or those with a narrow therapeutic range. Patients receiving smoking cessation agents may require periodic dose adjustments and closer clinical and laboratory monitoring of medications that are substrates of CYP450 1A2 or 1A1.
References (4)
- (2024) "Product Information. Cytisine (cytisinicline)." Consilient Health Ltd
- jeong sh, Newcombe D, sheridan j, Tingle M (2015) "Pharmacokinetics of cytisine, an a4 b2 nicotinic receptor partial agonist, in healthy smokers following a single dose." Drug Test Anal, 7, p. 475-82
- Vaughan DP, Beckett AH, Robbie DS (1976) "The influence of smoking on the intersubject variation in pentazocine elimination." Br J Clin Pharmacol, 3, p. 279-83
- Zevin S, Benowitz NL (1999) "Drug interactions with tobacco smoking: an update" Clin Pharmacokinet, 36, p. 425-38
cloZAPine food
Applies to: clozapine
MONITOR: Smoking cessation may lead to elevated plasma concentrations and enhanced pharmacologic effects of drugs that are substrates of CYP450 1A2 (and possibly CYP450 1A1) and/or certain drugs with a narrow therapeutic index (e.g., flecainide, pentazocine). One proposed mechanism is related to the loss of CYP450 1A2 and 1A1 induction by polycyclic aromatic hydrocarbons in tobacco smoke; when smoking cessation agents are initiated and smoking stops, the metabolism of certain drugs may decrease leading to increased plasma concentrations. The mechanism by which smoking cessation affects narrow therapeutic index drugs that are not known substrates of CYP450 1A2 or 1A1 is unknown. The clinical significance of this interaction is unknown as clinical data are lacking.
MANAGEMENT: Until more information is available, caution is advisable if smoking cessation agents are used concomitantly with drugs that are substrates of CYP450 1A2 or 1A1 and/or those with a narrow therapeutic range. Patients receiving smoking cessation agents may require periodic dose adjustments and closer clinical and laboratory monitoring of medications that are substrates of CYP450 1A2 or 1A1.
References (4)
- (2024) "Product Information. Cytisine (cytisinicline)." Consilient Health Ltd
- jeong sh, Newcombe D, sheridan j, Tingle M (2015) "Pharmacokinetics of cytisine, an a4 b2 nicotinic receptor partial agonist, in healthy smokers following a single dose." Drug Test Anal, 7, p. 475-82
- Vaughan DP, Beckett AH, Robbie DS (1976) "The influence of smoking on the intersubject variation in pentazocine elimination." Br J Clin Pharmacol, 3, p. 279-83
- Zevin S, Benowitz NL (1999) "Drug interactions with tobacco smoking: an update" Clin Pharmacokinet, 36, p. 425-38
cloZAPine food
Applies to: clozapine
Caffeine may increase clozapine serum concentrations and exacerbate psychotic symptoms. The mechanism is unknown but may be related to competition for the same metabolic pathway. No specific intervention is necessary; however, if an interaction is suspected it is recommended that caffeine intake be avoided.
References (4)
- Carrillo JA, Jerling M, Bertilsson L (1995) "Interaction between caffeine and clozapine - comment." J Clin Psychopharmacol, 15, p. 376-7
- Odom-White A, de Leon J (1996) "Clozapine levels and caffeine." J Clin Psychiatry, 57, p. 175-6
- Vainer JL, Chouinard G (1994) "Interaction between caffeine and clozapine." J Clin Psychopharmacol, 14, p. 284
- Hagg S, Spiset O, Mjorndal T, Dalqvist R (2000) "Effect of caffeine on clozapine pharmacokinetics in healthy volunteers." Br J Clin Pharmacol, 49, p. 59-63
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.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
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. | |
No interaction information available. |
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