Studies suggest that 14.5% of adults in the United States have experienced insomnia within the past 30 days.
Diphenhydramine is the active ingredient in Benadryl and the one that helps induce drowsiness and sleepiness.
The rules are different when Benadryl is used as a sleep aid.
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Arguably, the easiest way to dose Benadryl is by weight.
Take Benadryl 20 minutes before bedtime; sleepiness generally occurs within 30 minutes.
Benadryl tablets can be split, but tablets and capsules should be swallowed whole.

Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
Many of these side effects are dose-dependent, meaning that higher doses make them worse.
Overdosing
Never take more than the prescribed doses of Benadryl.
People who are smaller can sometimes overdose on amounts that are otherwise OK for larger people.
Speak with your obstetrician before using diphenhydramine in any form.
This is especially true in children.
Summary
Benadryl is an over-the-counter antihistamine with the active ingredient diphenhydramine.
Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
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