Drug interactions
Diphenhydramine + Etomidate
Severity: Moderate
Diphenhydramine and Etomidate: 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
Etomidate is an anesthetic induction agent, and a sedating antihistamine may add to its depressant effects. This can deepen sedation or prolong recovery, though the clinical effect is usually manageable in monitored settings.
What this interaction means in plain words
Diphenhydramine and Etomidate 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.
Diphenhydramine belongs to Respiratory; Etomidate belongs to Central Nervous System.
Why it happens
Additive CNS depression through GABA-A potentiation by etomidate and central H1 blockade.
What to do
Titrate etomidate to effect and monitor airway, ventilation and hemodynamics. Allow for prolonged recovery after recent diphenhydramine.
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 Etomidate
- Alprazolam + Etomidate Moderate
- Amitriptyline + Etomidate Moderate
- Amobarbital + Etomidate Moderate
- Azelastine + Etomidate Moderate
- Baclofen + Etomidate Moderate
- Brompheniramine + Etomidate Moderate
Frequently asked questions
Can I take Diphenhydramine with Etomidate?
MediHelp rates the interaction as moderate. Diphenhydramine and Etomidate 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. Etomidate is an anesthetic induction agent, and a sedating antihistamine may add to its depressant effects. This can deepen sedation or prolong recovery, though the clinical effect is usually manageable in monitored settings.
How serious is the interaction between Diphenhydramine and Etomidate?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Titrate etomidate to effect and monitor airway, ventilation and hemodynamics. Allow for prolonged recovery after recent diphenhydramine.
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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