Drug interactions
Clonidine + Clozapine
Severity: Major
Clonidine and Clozapine: major interaction.
Last updated Sources: US FDA label
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
Clozapine frequently causes orthostatic hypotension, sedation and sometimes bradycardia, all of which can be amplified by clonidine. The combination may lead to marked hypotension, syncope and falls.
What this interaction means in plain words
Clonidine and Clozapine can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Clonidine belongs to Cardiovascular; Clozapine belongs to Central Nervous System.
Why it happens
Additive hypotensive and sedative effects (clozapine alpha-1 blockade plus central alpha-2 agonism).
What to do
Monitor supine and standing blood pressure and heart rate closely, especially during clozapine titration. Reduce or stop clonidine if significant hypotension develops, tapering rather than stopping abruptly.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Clonidine
- Acebutolol + Clonidine Major
- Amifostine + Clonidine Major
- Amiodarone + Clonidine Major
- Amoxapine + Clonidine Major
- Atenolol-chlorthalidone + Clonidine Major
- Atenolol + Clonidine Major
Other interactions of Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
Frequently asked questions
Can I take Clonidine with Clozapine?
MediHelp rates the interaction as major. Clonidine and Clozapine can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Clozapine frequently causes orthostatic hypotension, sedation and sometimes bradycardia, all of which can be amplified by clonidine. The combination may lead to marked hypotension, syncope and falls.
How serious is the interaction between Clonidine and Clozapine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor supine and standing blood pressure and heart rate closely, especially during clozapine titration. Reduce or stop clonidine if significant hypotension develops, tapering rather than stopping abruptly.
What other medicines interact with Clonidine?
MediHelp also lists interactions of Clonidine with, for example, Acebutolol, Amifostine, Amiodarone. The full list is on the Clonidine page.
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