Can't sleep? Try an antihistamine

Aug 19, 2017

Can’t sleep? It happens to the best of us. Lack of sleep can interfere with most aspects of life. Your mood, appetite and ability to concentrate are a few things that can suffer when you haven’t made it to a full eight hours of sleep.

But what if we told you there was over-the-counter relief? This week, Dr. Elizabeth Higdon joins us to discuss the basics of sleep aids sold at your local pharmacy. Higdon is a community pharmacist and instructor in the Department of Pharmacy Practice at Albany College of Pharmacy and Health Sciences campus in Colchester, Vermont.

If you’ve ever taken an over-the-counter allergy medication, like an antihistamine, you know it makes you drowsy. But it isn’t just allergy sufferers who caught on to this phenomenon. Manufacturers also realized that the so-called side effects of an antihistamine can be used on their own, as a sleep aid.

“The most popular over-the-counter sleep aid is diphenhydramine, which is the active ingredient in Benadryl,” Higdon says.

“But Benadryl doesn’t make me sleepy…”

Although diphenhydramine is used at a much higher dose in over-the-counter sleep aids, not everyone suffers from the drowsy side-effects of the drug.

“They don’t experience the drowsiness,” Higdon says. “Some people actually have what’s called a paradoxical effect, this is typically seen more in children, but it makes them excited and they get a lot of energy, which is not something you’re looking for from a sleep aid.”

Others can build up a tolerance to the drowsiness and not reap the benefits of the side-effect anymore. Higdon recommends using a sleep aid for two or three nights and then taking a night off to see if the insomnia has resolved. That’s in order to prevent the efficacy from decreasing and because these sleep aids should really only be used in the short-term.

Side effects

Most unfortunate side effects, like sleep walking or sleep eating, have been seen with prescription sleep aids, like Ambien, according to Higdon. Similar side effects with an antihistamine are very rare.

“Instead with Benadryl you see more that patients build up a tolerance. So they take the 50 milligrams and it doesn’t cause them to sleep anymore,” she says.

You may experience what some call a “drug hangover” the next day if you’re sensitive to medicine or if you don’t give yourself enough time to sleep.

“Typically if you’re going to give yourself a sleep aid, you need to give yourself a full eight hours of sleep, Higdon says. “It’s not something that you want to take when you wake up at 2 a.m.”

Another important thing to note is that over-the-counter sleep aids can increase the occurrence of falls in those that are over 65-years-old, according to Higdon. She does not recommend this kind of antihistamine-based sleep aid for anyone over 65.