Diphenhydramine
Unisom is an over-the-counter sleep aid used to help adults and children 12 years and older fall asleep when experiencing occasional sleeplessness. It contains antihistamine ingredients and is intended for short-term use to promote restful sleep.
Unisom is an OTC sleep aid used to help relieve occasional sleeplessness.
Key facts at a glance
- RxNorm
- 220672
- Generic
- Unisom
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Unisom is used for the temporary relief of occasional sleeplessness in adults and children 12 years of age and older. It is not intended for long-term use or for treating underlying sleep disorders.
The active ingredients in Unisom products (such as doxylamine succinate or diphenhydramine) are antihistamines that have sedative properties. They work by affecting natural chemicals in the brain to promote drowsiness and help initiate sleep.
Unisom may cause drowsiness, so it should only be taken when you can dedicate 7-8 hours to sleep. Avoid alcohol and other CNS depressants while taking this medication. Consult a healthcare provider if sleeplessness persists for more than 2 weeks, as this may indicate an underlying condition. Not recommended during pregnancy without medical advice.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy