Drug interactions
Caffeine + Clozapine
Severity: Moderate
Caffeine and Clozapine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Caffeine is metabolised by CYP1A2 and competitively inhibits clozapine metabolism, so high intake can raise clozapine levels. Sudden changes in caffeine consumption, such as stopping, can change clozapine exposure and cause toxicity or loss of effect.
What this interaction means in plain words
Caffeine and Clozapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Caffeine belongs to Miscellaneous; Clozapine belongs to Central Nervous System.
Why it happens
Caffeine competitively inhibits CYP1A2, reducing clozapine clearance.
What to do
Advise a consistent daily caffeine intake. Monitor for clozapine adverse effects or consider checking clozapine levels if intake changes substantially.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
Other interactions of Caffeine
- Caffeine + Ephedrine Major
- Caffeine + Fezolinetant Major
- Caffeine + Methylenedioxymethamphetamine Major
- Caffeine + Selegiline transdermal Major
- Adenosine + Caffeine Moderate
- Benzphetamine + Caffeine Moderate
Frequently asked questions
Can I take Caffeine with Clozapine?
MediHelp rates the interaction as moderate. Caffeine and Clozapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Caffeine is metabolised by CYP1A2 and competitively inhibits clozapine metabolism, so high intake can raise clozapine levels. Sudden changes in caffeine consumption, such as stopping, can change clozapine exposure and cause toxicity or loss of effect.
How serious is the interaction between Caffeine and Clozapine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise a consistent daily caffeine intake. Monitor for clozapine adverse effects or consider checking clozapine levels if intake changes substantially.
What other medicines interact with Clozapine?
MediHelp also lists interactions of Clozapine with, for example, Deferiprone, Irinotecan, Pimozide. The full list is on the Clozapine page.
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