How Long Does Benadryl Make You Sleep For?

Answer

Benadryl (diphenhydramine) is a first-generation antihistamine and is commonly used as a sleep aid due to the sedation that it causes. In fact, it is a common ingredient in many over-the-counter sleep products, such as ZzzQuil.

When used for the treatment of insomnia, studies indicate that Benadryl can help you fall asleep faster (how fast you fall asleep is known as 'sleep latency') but it doesn't significantly increase total sleep time, if at all.

Instead of discussing how long Benadryl makes you sleep for, a more appropriate question would be to ask long do the effects of Benadryl last (with the answer being around four to six hours).

Benadryl For Sleep

While studies indicate that Benadryl can help reduce sleep latency (i.e. time to fall asleep), it doesn't have a significant effect on total sleep time. In studies that do show an increase in total sleep time, the average increase was only about 29 minutes more than usual. Other studies didn't find an increase in total sleep time at all.

In addition, studies have noted several negatives to using Benadryl for sleep. Not only do we become tolerant to the effects within a few days, but it may also reduce sleep quality. In the words of one study:

"In addition to the potential for rapid tolerance, studies have indicated that [Benadryl] diphenhydramine and doxylamine are only minimally effective in inducing sleep, may reduce sleep quality, and may cause residual drowsiness. Therefore, the use of these drugs in insomnia patients is not recommended."

As the above excerpt mentions, there is a concern that using Benadryl for insomnia may lead to next-day hangover effects and 'residual' drowsiness.

In terms of how long the effects of Benadryl last, it is only around 4 to 6 hours. Nevertheless, Benadryl is associated with next-day grogginess and decreased alertness, especially in the elderly, since they may metabolize the drug more slowly.

If you do choose to use Benadryl to help sleep, it shouldn't be used more than on an 'as needed' basis. You also shouldn't expect to make you sleep longer than usual. If you have consistent issues with sleep, you should speak to your doctor about more effective therapies.

Lastly, Midol (the other drug in question) should not have significant sedative effects.

Final Words

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