Drug interactions
Dextromoramide + Diphenhydramine
Severity: Major
Dextromoramide and Diphenhydramine: major 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
Dextromoramide is a potent opioid analgesic, and diphenhydramine is a sedating antihistamine. Together they increase sedation and can depress breathing. The risk is greater at higher opioid doses and in older or frail patients.
What this interaction means in plain words
Dextromoramide and Diphenhydramine 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 central nervous system and respiratory depression from opioid agonism and central H1 blockade.
What to do
Avoid regular use of sedating antihistamines with this opioid. If both are needed, use the lowest effective doses and monitor sedation and respiratory rate.
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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Other interactions of Diphenhydramine
Frequently asked questions
Can I take Dextromoramide with Diphenhydramine?
MediHelp rates the interaction as major. Dextromoramide and Diphenhydramine 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. Dextromoramide is a potent opioid analgesic, and diphenhydramine is a sedating antihistamine. Together they increase sedation and can depress breathing. The risk is greater at higher opioid doses and in older or frail patients.
How serious is the interaction between Dextromoramide and Diphenhydramine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid regular use of sedating antihistamines with this opioid. If both are needed, use the lowest effective doses and monitor sedation and respiratory rate.
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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