Haloperidol carbamazepine

There are reports of interactions between lithium and carbamazepine, haloperidol, digoxin, and verapamil resulting in a variety of neurotoxic and cardiotoxic effects. These are not common interactions but clearly indicate a need for caution if such drug combinations are unavoidable. Anticonvulsants... 

A 59-year-old man who had been diagnosed with encephalopathy and confusion while taking a combination of carbamazepine, haloperidol and lithium (therapeutic lithium level), developed similar symptoms when he was later given lithium with olanzapine. Another elderly patient who had taken lithium for 7 years, developed severe delirium and extrapyramidal... 

Haverkos HW, Pinsky PF, Drotman DP, etal Disease manifestation among homosexual men with acquired immunodeficiency syndrome a possible role of nitrites in Kaposi s sarcoma. Sex Transm Dis 12 203-208, 1985 Haverkos HW, Kopstein AN, Wilson H, et al Nitrite inhalants history, epidemiology, and possible links to AIDS. Environ Health Perspect 102 858-861, 1994 Hernandez-Avila CA, Ortega-Soto HA, Jasso A, et al Treatment of inhalant-induced psychotic disorder with carbamazepine versus haloperidol. Psychiatr Serv49 812— 815, 1998... 

CYP3A4 TCAs, risperidone, carbamazepine, benzodiazepines, haloperidol, fluoxetine,... 

Chronic Agitation. For chronic agitation with physical aggression, sodium divalproex is the preferred treatment. If divalproex is ineffective, haloperidol or an atypical antipsychotic can be added or snbstituted. Other options include trazodone, carbamazepine, and SSRI antidepressants. 

Codeine, dextromethorphan, haloperidol, thioridazine, perphenazine, nortriptyline, desipramine, fluoxetine, norfluoxetine, TCAs (hydroxylation), beta-blockers such as timolol and metoprolol, type 1C antiarrhythmics encainide, flecainide TCAs (desmethylation), triazolam, alprazolam, midazolam, carbamazepine, terfenadine, quinidine, lidocaine, erythromycin, cyclosporin... 

Largactil is a proprietary preparation of chlorpromazine, an aliphatic antipsychotic with marked sedation and moderate antimuscarinic and extrapyramidal side-effects. Serenace is a proprietary preparation of haloperidol, a butyrophenone antipsychotic with marked extrapyramidal side-effects, moderate sedation but not very likely to cause hypotension. Tegretol is a proprietary preparation of carbamazepine, an anti-epileptic drug indicated in partial and secondary generalised tonic-clonic seizures, primary generalised tonic-clonic seizures, trigeminal neuralgia and in the prophylaxis of bipolar disorder unresponsive to lithium. 

Drugs that may affect tricyclic compounds include barbiturates, carbamazepine, charcoal, cimetidine, haloperidol, histamine H2-antagonists, MAO inhibitors,... 

Drugs that affect nefazodone include general anesthetics, sibutramine, sumatriptan, buspirone, carbamazepine, and propranolol. Drugs that may be affected by nefazodone include alcohol, benzodiazepines, buspirone, carbamazepine, cisapride, digoxin, haloperidol, HMG-CoA reductase inhibitors, MAOIs, propranolol, St. John s wort, cyclosporine, and tacrolimus. 

Drugs that may be affected by SSRIs Drugs that may be affected by SSRIs include alcohol, benzodiazepines, beta blockers, buspirone, carbamazepine, cisapride, clozapine, cyclosporine, diltiazem, digoxin, haloperidol, hydantoins, lithium, methadone, mexiletine, nonsedating antihistamines, NSAIDs, olanzapine, phenothiazines, phenytoin, pimozide, procyclidine, ritonavir, ropivacaine, sumatriptan, sulfonylureas, sympathomimetics, tacrine, theophylline, tolbutamide, tricyclic antidepressants, and warfarin. 

Drugs that may affect lithium include acetazolamide, carbamazepine, fluoxetine, haloperidol, loop diuretics, methyidopa, NSAIDs, osmotic diuretics, theophyllines. 

Acetaminophen Amiodarone Carbamazepine Cardiac glycosides Corticosteroids Dicumarol Disopyramide Doxycycline Estrogens Haloperidol Methadone Metyrapone Mexiletine Oral contraceptives Quinidine Theophylline Valproic acid Cyclosporine Dopamine Furosemide Levodopa Levonorgestrel Mebendazole Nondepolarizing muscle relaxant Phenothiazines Sulfonylureas... 

Drugs that can decrease carbamazepine serum levels include charcoal, cisplatin, doxorubicin, felbamate, hydantoins, rifampin, phenobarbital, primidone, theophylline. The serum levels of oral contraceptives, haloperidol, bupropion, anticoagulants, felbamate, valproic acid, felodipine, tricyclic antidepressants, acetaminophen, ziprasidone, voriconazole, topiramate, tiagabine, olanzapine, and lamotrigine can be lowered by carbamazepine. 

Drugs that may be affected by itraconazole include alfentanil, almotriptan, alprazolam, amphotericin B, aripiprazole, benzodiazepines, buspirone, busulfan, calcium blockers, carbamazepine, cilostazol, cisapride, corticosteroids, cyclosporine, digoxin, disopyramide, docetaxel, dofetilide, eletriptan, epierenone, ergot alkaloids, haloperidol, HMG-CoA reductase inhibitors, hydantoins (phenytoin), hypoglycemic agents, oral midazolam, phosphodiesterase type 5 inhibitors, pimozide, polyenes, protease inhibitors, quinidine, rifamycins, sirolimus, tacrolimus, tolterodine, triazolam, trimetrexate, vinca alkaloids, warfarin, and zolpidem. 

Arana, G.W., Goff, D.C., Friedman, H., Ornsteen, M., Greenblatt, D.J., Black, B., and Shader, R.I. (1986) Does carbamazepine-induced reduction of plasma haloperidol levels worsen psychotic symptoms Am Psychiatry 143 650-651. 

Brown, D., Silverstone, T., and Cookson, J. (1989) Carbamazepine compared to haloperidol in acute mania. Int Clin Psychopharmacol 4 229-238. 

Brown AS, GershonS Dopamine and depression. J Neural Transm 91 75-109, 1993 Brown D, Silverstone T, Cookson J Carbamazepine compared to haloperidol in acute mania. Int Clin Psychopharmacol 4 229-238, 1989 Brown CM Endocrine aspects of psychosocial dwarfism, in Hormones, Behavior, and Psychopathology. Edited by Sachar E. New York, Raven, 1975 Brown GR, RundeU JR A prospective study of psychiatric aspects of early HIV disease in women. Gen Hosp Psychiatry 15 139-147, 1993 Brown GW, Harris TO Aetiology of anxiety and depressive disorders in an inner-city population, 1 early adversity. Psychol Med 23 143-154, 1993 Brown GW, Harris T, Copeland JR Depression and loss. Br J Psychiatry 130 1-18, 1977... 

Klein E, Bental E, Lerer B, et al Carbamazepine and halopeiidol vs. placebo and haloperidol in excited psychoses. Arch Gen Psychiatry 41 165-170, 1984a Klein E, Hefez A, Lavie P Effects of clomipramine infusion on sleep in depressed patients. Neuropsychobiology 1 85-88, 1984b Klein E, Lavie P, Meiraz R, et al Increased motor activity and recurrent manic episodes risk factors that predict rapid relapse in remitted bipolar disorder patients after lithium discontinuation—a double blind study. Biol Psychiatry 31 279-284, 1992... 

Moller HJ, Kissling W, Riehl T, et al Double blind evaluation of the antimanic properties of carbamazepine as a comedication to haloperidol. Prog Neuropsycho-pharmacol Biol Psychiatry 13 127-136, 1989... 

Oxcarbazepine is a keto derivative of carbamazepine but offers several advantages over carbamazepine. Oxcarbazepine does not require blood cell count, hepatic, or serum drug level monitoring. It causes less cytochrome P450 enzyme induction than does carbamazepine (but may decrease effectiveness of oral contraceptives containing ethinyl estradiol and levonorgestrel). As opposed to carbamazepine, oxcarbazepine does not induce its own metabolism. These properties, combined with its similarity to carbamazepine, led many clinicians to use this medication for the treatment of bipolar disorder. Randomized controlled trials suggested efficacy in the treatment of acute mania compared with lithium and haloperidol, but these trials were quite small and did not include a placebo control (Emrich 1990). 

Another use of the laboratory is for therapeutic drug monitoring (TDM) of psychotropics with defined optimal ranges, narrow therapeutic indices, or both. Although TDM is not essential for many psychotropics, it is for others, including lithium, several TCAs, valproate, and carbamazepine. It may also be helpful to optimize the use of certain antipsychotics (e.g., haloperidol, clozapine) ( 7). 

Antipsychotics. Clear guidelines for measuring therapeutic serum concentrations of antipsychotics have not yet been established. There may, however, be specific situations in which they may be of value (e.g., monitoring of haloperidol [HPDL] levels might be useful in patients on concurrent carbamazepine therapy because the latter agent can substantially reduce serum HPDL concentrations). These issues are discussed in greater detail in the Pharmacokinetics/Plasma Level section in Chapter 5. 

The use of two or more agents concurrently has the potential for possibly deleterious drug interactions. Thus, as noted in subsequent chapters, the addition or elimination of an agent may significantly alter the activity of the concurrent drug treatment (e.g., carbamazepine lowering haloperidol plasma levels nefazodone increasing the levels of triazolam). 

Limited evidence indicates that carbamazepine plus an antipsychotic may also benefit some schizophrenic patients. This is an interesting possibility in view of the similar antimanic properties of lithium and carbamazepine (375). This area requires further research, especially to clarify the indications for combining anticonvulsants with an antipsychotic. For example, mania complicated by psychotic features may benefit from lithium, valproate, or carbamazepine augmented by antipsychotics. Because carbamazepine induces the metabolism of at least some antipsychotics (e.g., haloperidol, thiothixene), dose adjustment based on TDM may be necessary to achieve the optimal effect. 

Kidron R, Averbuch I, Klein E, et al. Carbamazepine-induced reduction of blood levels of haloperidol in chronic schizophrenia. Biol Psychiatry 1985 20 219-222. 

Klein E, Bental E, Lerer B, et al. Carbamazepine and haloperidol versus placebo and haloperidol in excited psychoses. Arch Gen Psychiatry 1984 41 165-170. 

Kahn EM, Schulz SC, Perel JM, et al. Change in haloperidol level due to carbamazepine—a complicating factor in combined medication for schizophrenia. 

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