Drug interactions
Diamorphine + Quetiapine
Severity: Major
Diamorphine and Quetiapine: 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
Combining quetiapine with diamorphine (heroin) produces additive sedation and may cause profound drowsiness, hypotension and respiratory depression. The risk is greatest in the elderly, in opioid-naive patients and at higher doses.
What this interaction means in plain words
Diamorphine and Quetiapine 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.
Why it happens
Additive CNS and respiratory depression from opioid agonism and the sedative and hypotensive receptor effects of quetiapine.
What to do
Use the lowest effective doses and monitor sedation, respiratory rate and blood pressure closely. Avoid other CNS depressants where possible.
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 Quetiapine
- Adagrasib + Quetiapine Major
- Amiodarone + Quetiapine Major
- Amisulpride + Quetiapine Major
- Amoxapine + Quetiapine Major
- Anagrelide + Quetiapine Major
- Apalutamide + Quetiapine Major
Frequently asked questions
Can I take Diamorphine with Quetiapine?
MediHelp rates the interaction as major. Diamorphine and Quetiapine 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. Combining quetiapine with diamorphine (heroin) produces additive sedation and may cause profound drowsiness, hypotension and respiratory depression. The risk is greatest in the elderly, in opioid-naive patients and at higher doses.
How serious is the interaction between Diamorphine and Quetiapine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lowest effective doses and monitor sedation, respiratory rate and blood pressure closely. Avoid other CNS depressants where possible.
What other medicines interact with Quetiapine?
MediHelp also lists interactions of Quetiapine with, for example, Adagrasib, Amiodarone, Amisulpride. The full list is on the Quetiapine page.
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