Skip to main content

Diphenhydramine: 7 things you should know

Medically reviewed by Carmen Pope, BPharm. Last updated on July 26, 2023.

1. How it works

2. Upsides

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects

4. Bottom Line

Diphenhydramine is an antihistamine that can be used to treat allergic reactions, relieve motion sickness, as a sleep aid, and relieve some symptoms of Parkinson's disease. Sedation is a common side effect.

5. Tips

6. Response and effectiveness

7. Interactions

Medicines that interact with diphenhydramine may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with diphenhydramine. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with diphenhydramine include:

Alcohol may enhance the sedative effects of diphenhydramine.

Note that this list is not all-inclusive and includes only common medications that may interact with diphenhydramine. You should refer to the prescribing information for diphenhydramine for a complete list of interactions.

References

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use diphenhydramine only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2024 Drugs.com. Revision date: July 25, 2023.