Drug interactions
Apomorphine + Diphenhydramine
Severity: Moderate
Apomorphine and Diphenhydramine: 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
Both agents can cause drowsiness, and apomorphine may also cause sudden sleep onset and orthostatic hypotension. Diphenhydramine may add to sedation and dizziness, and its anticholinergic action can counter dopaminergic benefit in Parkinson disease.
What this interaction means in plain words
Apomorphine and Diphenhydramine 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.
Apomorphine belongs to Central Nervous System; Diphenhydramine belongs to Respiratory.
Why it happens
Additive CNS depression, with anticholinergic effects opposing dopaminergic therapy.
What to do
Monitor for excessive sedation, falls and hypotension. Avoid regular diphenhydramine in patients with Parkinson disease where alternatives exist.
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 Diphenhydramine
Other interactions of Apomorphine
- Alosetron + Apomorphine Contraindicated
- Apomorphine + Cisapride Contraindicated
- Apomorphine + Dolasetron Contraindicated
- Apomorphine + Granisetron Contraindicated
- Apomorphine + Netupitant-palonosetron Contraindicated
- Apomorphine + Ondansetron Contraindicated
Frequently asked questions
Can I take Apomorphine with Diphenhydramine?
MediHelp rates the interaction as moderate. Apomorphine and Diphenhydramine 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. Both agents can cause drowsiness, and apomorphine may also cause sudden sleep onset and orthostatic hypotension. Diphenhydramine may add to sedation and dizziness, and its anticholinergic action can counter dopaminergic benefit in Parkinson disease.
How serious is the interaction between Apomorphine and Diphenhydramine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for excessive sedation, falls and hypotension. Avoid regular diphenhydramine in patients with Parkinson disease where alternatives exist.
What other medicines interact with Diphenhydramine?
MediHelp also lists interactions of Diphenhydramine with, for example, Alfentanil, Belladonna and opium, Benzhydrocodone / acetaminophen. The full list is on the Diphenhydramine page.
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