Drug interactions
Desipramine + Diphenhydramine
Severity: Moderate
Desipramine 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
Diphenhydramine inhibits CYP2D6 and may raise desipramine concentrations, increasing the risk of tricyclic toxicity. Both drugs are also sedating and anticholinergic, so confusion, urinary retention and tachycardia are more likely.
What this interaction means in plain words
Desipramine 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.
Desipramine belongs to Central Nervous System; Diphenhydramine belongs to Respiratory.
Why it happens
CYP2D6 inhibition by diphenhydramine plus additive CNS depression and anticholinergic effects.
What to do
Avoid regular combined use, especially in older adults; if needed, monitor for anticholinergic and cardiac toxicity and consider checking desipramine levels.
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 Desipramine
- Desipramine + Disopyramide Contraindicated
- Desipramine + Dofetilide Contraindicated
- Desipramine + Ibutilide Contraindicated
- Desipramine + Isocarboxazid Contraindicated
- Desipramine + Methylene blue Contraindicated
- Desipramine + Pentamidine Contraindicated
Other interactions of Diphenhydramine
Frequently asked questions
Can I take Desipramine with Diphenhydramine?
MediHelp rates the interaction as moderate. Desipramine 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. Diphenhydramine inhibits CYP2D6 and may raise desipramine concentrations, increasing the risk of tricyclic toxicity. Both drugs are also sedating and anticholinergic, so confusion, urinary retention and tachycardia are more likely.
How serious is the interaction between Desipramine 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: Avoid regular combined use, especially in older adults; if needed, monitor for anticholinergic and cardiac toxicity and consider checking desipramine levels.
What other medicines interact with Desipramine?
MediHelp also lists interactions of Desipramine with, for example, Disopyramide, Dofetilide, Ibutilide. The full list is on the Desipramine page.
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