Cimetidine Bupropion

Because bupropion is extensively metabolized, the coadministration of other drugs may affect its clinical activity. In particular, certain drugs may induce the metabolism of bupropion (eg, carbamazepine, phenobarbital, phenytoin) while other drugs may inhibit the metabolism of bupropion (eg, cimetidine, ritonavir). 

Because bupropion is metabolized in the liver, medications that alter hepatic enzyme metabolism, such as carbamazepine or cimetidine, may effect blood concentrations. Bupropion should not be administered in combination with the MAOIs because of risk of hypertensive crisis. Levo-dopa use in conjunction with bupropion has been associated with confusion, hallucinations, and dyskinesia. Although generally well tolerated, there are case reports documenting that the... 

D6 Tricyclic antidepressants (TCAs), benztropine, perphenazine, clozapine, haloperidol, codeine/oxycodone, risperidone, class Ic antiarrhythmics, 3 blockers, trazodone, paroxetine, maprotiline, amoxapine, duloxetine, mirtazapine (partly), venlafaxine, bupropion Fluoxetine, paroxetine, duloxetine, hydroxybupropion, methadone, cimetidine, haloperidol, quinidine, ritonavir Phenobarbital, rifampin... 

H2 RECEPTOR BLOCKERS DRUG DEPENDENCE THERAPIES-BUPROPION t plasma concentrations of cimetidine and ranitidine Bupropion and its metabolite hydroxybupropion inhibit CYP2D6 Initiate therapy of these drugs at the lowest effective dose... 

Fluoxetine, paroxetine, bupropion, duloxetine, and other CYP450 2D6 inhibitors may increase TCA concentrations Cimetidine may increase plasma concentrations of TCAs and cause anticholinergic symptoms Phenothiazines or haloperidol may raise TCA blood concentrations May alter effects of antihypertensive drugs may inhibit hypotensive effects of clonidine Use of TCAs with sympathomimetic agents may increase sympathetic activity Methylphenidate may inhibit metabolism of TCAs... 

Clopixol—Acuphase Clopixol Depot Clopixol tablets lincomycin piroxicam bupropion acyclovir collagen hydrocodone zileuton allopurinol allopurinol pancrelipase cimetidine nicorandil naloxone collagen olanzapine cetirizine linezolid... 

General enzyme inducers co-administered with bupropion could theoretically induce the metabolism of bupropion. However, results of clinical studies have been inconsistent regarding this possibility. For example, cimetidine has not been found to affect the pharmacokinetics of bupropion. 

A randomised, open-label, crossover study in 24 healthy subjects found no evidence of any signiflcant pharmacokinetic interaction between a single 300-mg dose of bupropion (sustained release preparation) and a single 800-mg dose of cimetidine. No special precautions would seem to be necessary on concurrent use. 

Kustra R, Corrigan B, Dunn J, Duncan B, Hsyu P-H, Lack of effect of cimetidine on the pharmacokinetics of sustained-release bupropion, J Clin Pharmacol (1999) 39,1184-8,... 

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