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Drug Class
Antihistamine
Common Uses
- Allergies
- Insomnia
Common Brand Names
Benadryl, Phenz
Overview
Diphenhydramine is an antihistamine medicine that relieves the symptoms of allergies. It's known as a drowsy (sedating) antihistamine and is more likely to make you feel sleepy than other antihistamines. It's used for:
- short-term sleep problems (insomnia), including when a cough, cold or itching is keeping you awake at night
- cough and cold symptoms
- hay fever
- eczema, hives (urticaria) and insect bites and stings
Important Facts
- To help you sleep, you'll usually take diphenhydramine 20 minutes before you go to bed. It normally takes about 30 minutes to work.
- Common side effects include feeling sleepy, dizzy or unsteady on your feet. You may also have difficulty concentrating and have a dry mouth.
- You can become dependent on diphenhydramine if you take it continuously for a period of time. It may also stop working as well. Speak to your doctor if you need to take it for more than 2 weeks.
- Do not drink alcohol while taking diphenhydramine. Alcohol increases the risk of side effects.
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