Clozapine and Naltrexone and bupropion interaction

Clozapine and Naltrexone and bupropion: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.

Moderate

Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.

What the FDA labels say

From the Clozapine (Clozaril) label · effective 2025-06-06

Moderate

CYP2D6 and CYP3A4 Inhibitors Concomitant treatment with CLOZARIL and CYP2D6 or CYP3A4 inhibitors (e.g., cimetidine, escitalopram, erythromycin, paroxetine, bupropion, fluoxetine, quinidine, duloxetine, terbinafine, or sertraline) can increase clozapine levels and lead to adverse reactions [see Clinical Pharmacology ( 12.3 )] .

Drug interactionsnames Naltrexone and bupropionView label on DailyMed
Minor

Such drugs include specific antidepressants, phenothiazines, carbamazepine, and Type 1C antiarrhythmics (e.g., propafenone, flecainide, and encainide).

Drug interactionsby drug classView label on DailyMed

From the Naltrexone and bupropion (Contrave Extended-Release) label · effective 2025-11-10

Moderate

…medications (sulfonylureas and meglitinides) that may cause hypoglycemia concomitant administration of medications that may lower the seizure threshold, including other bupropion products, antipsychotics, tricyclic antidepressants, theophylline, systemic steroids Recommendations for Reducing the Risk of Seizure: Clinical experience with bupropion suggests that the risk…

Warnings and precautionsby drug classView label on DailyMed
Moderate

Drugs Metabolized by CYP2D6: Bupropion inhibits CYP2D6 and can increase concentrations of antidepressants, (e.g., selective serotonin reuptake inhibitors and many tricyclics), antipsychotics (e.g., haloperidol, risperidone and thioridazine), beta-blockers (e.g., metoprolol) and Type 1C antiarrhythmics (e.g., propafenone and flecainide).

Drug interactionsby drug classView label on DailyMed
Moderate

Coadministration of CONTRAVE with drugs that are metabolized by CYP2D6 isozyme including certain antidepressants (SSRIs and many tricyclics), antipsychotics (e.g., haloperidol, risperidone and thioridazine), beta-blockers (e.g., metoprolol) and Type 1C antiarrhythmics (e.g., propafenone and flecainide), should be approached with caution and should be initiated…

Drug interactionsby drug classView label on DailyMed
Moderate

Drugs That Lower Seizure Threshold Use extreme caution when coadministering CONTRAVE with other drugs that lower seizure threshold (e.g., antipsychotics, antidepressants, theophylline, or systemic corticosteroids).

Drug interactionsby drug classView label on DailyMed

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Not medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.