Clozapine and Smoking Cessation: Drug Interaction Guide

Quick answer: This combination requires caution. Clozapine and Smoking Cessation can be used together with adjustments and monitoring.

Interaction severity: Moderate — caution required

How Clozapine interacts with Smoking Cessation

Polycyclic aromatic hydrocarbons in tobacco smoke induce CYP1A2, the main enzyme metabolising clozapine; abrupt smoking cessation removes induction and can double clozapine levels within a week.

What you should do

Anticipate dose reduction of approximately 30-50% on stopping smoking; measure clozapine level within 5-7 days and monitor for sedation, hypotension and seizures.

Key facts

Severity

Moderate — caution required

Mechanism

Polycyclic aromatic hydrocarbons in tobacco smoke induce CYP1A2, the main enzyme metabolising clozapine; abrupt smoking ...

Action

Anticipate dose reduction of approximately 30-50% on stopping smoking; measure clozapine level within 5-7 days and monit...

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Clozapine and Smoking Cessation together?

With caution. Anticipate dose reduction of approximately 30-50% on stopping smoking; measure clozapine level within 5-7 days and monitor for sedation, hypotension and seizures.

What is the severity of this interaction?

The interaction between Clozapine and Smoking Cessation is classified as Moderate — caution required. Polycyclic aromatic hydrocarbons in tobacco smoke induce CYP1A2, the main enzyme metabolising clozapine; abrupt smoking cessation removes induction and can double clozapine levels within a week.

What should I do if I'm prescribed both?

Anticipate dose reduction of approximately 30-50% on stopping smoking; measure clozapine level within 5-7 days and monitor for sedation, hypotension and seizures. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.