Drug interactions
Diethylpropion + Diphenhydramine
Severity: Minor
Diethylpropion and Diphenhydramine: minor 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
Diethylpropion is a stimulant appetite suppressant, and diphenhydramine is a sedating antihistamine. The stimulant effect may partly offset the sedation. No clinically important interaction has been well established.
What this interaction means in plain words
Diethylpropion and Diphenhydramine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Opposing central nervous system effects; no established pharmacokinetic mechanism.
What to do
No action is generally needed. Advise the patient that sedation or stimulation may be altered.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Diphenhydramine
Frequently asked questions
Can I take Diethylpropion with Diphenhydramine?
MediHelp rates the interaction as minor. Diethylpropion and Diphenhydramine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Diethylpropion is a stimulant appetite suppressant, and diphenhydramine is a sedating antihistamine. The stimulant effect may partly offset the sedation. No clinically important interaction has been well established.
How serious is the interaction between Diethylpropion and Diphenhydramine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No action is generally needed. Advise the patient that sedation or stimulation may be altered.
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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