Children's Hospital Colorado

Diphenhydramine (Benadryl)

Disclaimer: The below information is not intended as a substitute for professional medical advice. It is provided for educational and reference purposes only. You assume full responsibility for how you choose to use this information. Please call your primary care provider or our ParentSmartTM Healthline with any questions. Pediatric nurses are available 24/7 at 720-777-0123.

You can take diphenhydramine if you have itching from insect bites, poison ivy, hives, or other itchy rashes.

You can also take it to relieve allergy and hay fever symptoms like:

  • Red, itchy, watery eyes
  • Runny nose
  • Sneezing


  • Benadryl: Take 1-2 pills (25-50 mg) every 4 to 6 hours as needed. Each pill has 25 mg of diphenhydramine. Do not take more than 12 pills (300 mg) per day.

Extra Notes and Warnings:

  • This is an over-the-counter (OTC) drug. You can buy it at the drugstore.
  • This type of drug is an antihistamine.
  • This type of drug may cause you to feel sleepy. Do not drink alcohol, drive, or use dangerous machinery while taking it.
  • Do not take this drug if you have an enlarged prostate.

Common Brand Names:

  • Aler-Dryl
  • Benadryl

Read the instructions and warnings on the package insert for all medicines you take.