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The Lowdown on Over-the-Counter Sleep Aids

A discussion of the pros/cons to taking them

Upwards of 50% of Americans have experienced occasional insomnia and 15% of them have sleeplessness that occurs on a chronic basis. As a result, the sleep aid industry is booming. We’re bombarded with ads for the next miracle to help us sleep perfectly – from the ideal pillow to the latest herbal remedy to prescription medications.

Many people with insomnia first turn to over-the-counter (OTC) methods to help them sleep better: alcohol (not a good remedy since it worsens sleep quality), relaxation strategies, proper sleep hygiene, and OTC medications. Although OTCs may be helpful for the occasional sleepless night, they are not ideal treatments for those with chronic insomnia (e.g. those who experience sleep loss on a regular basis for as few as 2 weeks).

Just because something is sold OTC doesn’t mean it is without side effects. In addition, many OTCs can have negative interactions with other medications you may currently be taking. Below, I’ll list the most commonly taken OTCs and discuss the pros/cons with their use. Look at the active ingredient label on the OTCs to see if they contain any of the ones listed below.

1. Diphenhydramine (Nyquil ZZZ, Tylenol PM, Advil PM, Benadryl, Unisom Sleep): Diphenhydramine is a sedating antihistamine that creates drowsiness for some who take it. It may be helpful for occasional bouts of insomnia, but the biggest concern with taking it regularly (two or more weeks of regular use) it that tolerance can develop to the medication and any sedating effects tend to wear off. As a result, a psychological dependence may be formed for the medication (you think you need it, but most often the drowsy effects from the medication don’t really happen anymore). You also might start to take more of the medication to experience the same sleep-inducing effects. In addition, patients often report feeling drowsy and drained in the morning. Side effects commonly include dizziness, feeling “off” the next day, grogginess, dry mouth and memory problems.

2. Melatonin: Melatonin is a natural hormone produced by the pineal gland in the brain. Commonly referred to as the “hormone of darkness,” melatonin is produced in our brain when the sun goes down, therefore inducing sleepiness within a few hours. When we wake up in the morning and are exposed to light, melatonin production is stopped. Studies generally do not support the effectiveness of melatonin (typically between 3mg and 10mg) as a treatment for chronic insomnia. In my clinical practice, I’ve come across a limited few patients who do find it helpful, but I’d say that this has definitely been the minority. Further, melatonin is not currently regulated by the FDA. The formulations and potencies can actually vary from bottle to bottle without regulation. Side effects may include daytime sleepiness, headaches, confusion, sleepwalking, nightmares and nausea. It may also interact negatively with certain medications (diabetes medications, immunosuppressants, birth control pills, blood thinners).

When taken in very low dosages (0.5mg-3mg), melatonin has been shown to be very effective for those with circadian rhythm disorders such as jet lag and delayed sleep phase disorder. If you suffer from a circadian rhythm issue, talk with a sleep specialist to discuss the proper time to take melatonin (taking it just before bed isn't advised for this population).

3. Doxylamine (Unisom Sleep Tabs): Another sleep-inducing OTC medication, its side effect profile is similar to that of diphenhydramine (discussed above).

4. Valerian: Limited research has shown some sleep benefits in taking valerian, and it might be useful for those who have occasional sleepless nights. Just like with melatonin, it is not regulated by the FDA and the potency can vary significantly between manufacturers. Research is rather new in this field and, though some suggest it as a possible treatment for insomnia, there’s not enough positive study support to make it a standard recommendation in the field. Side effects typically include excitability, nausea, uneasiness and headache.

If you are considering taking an OTC sleep aid, talk with your doctor to figure out the best plan to treat your insomnia. OTCs might be useful for very occasional bouts of insomnia, but other treatments such as cognitive behavior therapy for insomnia or prescription sleep aids may be more appropriate given your personal medical and psychiatric history. If you already have been taking OTCs on a regular basis for over 2 weeks, definitely discuss other treatment options with your doctor. Don’t mix OTCs with alcohol and be cautious of driving or operating any heavy machinery if you feel groggy as a side effect. Finally, if you are struggling with obtaining a good night’s sleep, talk with your doctor about getting a referral to a sleep specialist. Many good treatments are available for sleep disorders, and you shouldn’t suffer in silence.

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