The usual dosage of diphenhydramine for treating insomnia is 50 mg taken 30 minutes before bedtime. The recommended dosage for the treatment of allergy or cold symptoms is 25 to 50 mg every four to six hours. For topical forms of the drug, dosing varies depending on the particular product; a small amount should be applied to the skin no more than three or four times daily.
Dosage of Diphenhydramine: An Introduction
The recommended dose of diphenhydramine (Benadryl®, Sominex®, and many other brand names) will vary, depending on a number of factors, including:
- The medical condition being treated
- The particular product
- Your age
- How you respond to diphenhydramine
- Other medications you are taking
- Other medical conditions you may have.
As is always the case, do not adjust your dosage unless your healthcare provider specifically instructs you to do so.
Dosing for Sleep
The usual diphenhydramine dose for insomnia in adults is 50 mg taken 30 minutes before bedtime. Elderly people (or those who seem to be sensitive to the effects of this medication) may find a lower dose (25 mg) to be more tolerable.
Dosing for Allergies or Cold Symptoms
The recommended diphenhydramine dosage for treating allergy or common cold symptoms in adults and children ages 12 years and older is 25 to 50 mg every four to six hours. For children ages 6 to 12 years old, the recommended dosage is 12.5 to 25 mg every four to six hours.
Dosing for Allergic Reactions or Motion Sickness
The recommended diphenhydramine dosage for treating allergic reactions or motion sickness in adults is 25 to 50 mg every six to eight hours.