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Over the Counter Sleep Aids
Many people take sleeping pills in order to fall asleep more quickly and get enough rest. Some sleep medications, such as orexin receptor antagonists and benzodiazepines, require a doctor’s prescription. Other types of sleep aids are available over-the-counter (OTC) without a prescription and can be used to treat insomnia and other sleep issues, but you should still exercise caution and speak to a doctor about risk factors, side effects, and other potential concerns before taking these medications for the first time.
Which OTC Sleep Aids Are Available?
While you can choose from dozens of different brand names, most OTC sleep aids fall into one of the following categories based on their chemical composition. Always consult a physician , whether or not it requires a prescription.
Melatonin
Melatonin is a natural hormone produced in the pineal gland of the brain . During the day, the retinas perceive the presence of natural light and signal the brain to secrete hormones like cortisol that promote feelings of wakefulness and alertness. As daylight fades in the evening, the pineal gland receives signals to release melatonin, which makes you feel tired and relaxed.
Certain factors can hinder or decrease melatonin production , such as exposure to light in the evening that essentially confuses the brain into thinking you should feel awake. To boost low melatonin levels, some people take melatonin supplements. These supplements may be made from animals, microorganisms, or – most often – synthetic components.
Melatonin may be recommended or prescribed for certain conditions. These include circadian rhythm sleep disorders that reduce your melatonin levels , such as delayed sleep-wake phase disorder or shift work disorder, as well as certain sleep disorders in children. Melatonin may also improve symptoms for travelers experiencing jet lag.
The U.S. Food and Drug Administration (FDA) classifies melatonin as a dietary supplement and does not regulate it as strictly as other types of medication. Physicians advise that melatonin carries an allergy risk for some individuals. People with epilepsy and those who take blood-thinning medication should also be under medical supervision while taking melatonin in order to avoid potentially dangerous interactions.
Diphenhydramine
Diphenhydramine is an FDA-approved antihistamine commonly marketed under the brand name Benadryl. It is found in a wide variety of brand-name OTC pain-relieving or fever-reducing medications , including Advil PM, Excedrin PM, Nytol, Tylenol PM, and ZzzQuil.
Medications with diphenhydramine may be recommended or prescribed for occasional bouts of sleepiness.
The efficacy of diphenhydramine as a sleep aid is debatable. Some studies have administered the recommended dose of 50mg to participants, and results suggest sleep improvements are limited at best. At the same time, diphenhydramine taken at night has been associated with psychomotor impairments and reduced wakefulness the following day.
Some studies have found that a relatively large number of older adults may chronically take medications with diphenhydramine for insomnia treatment or self-care. Elderly people are at higher risk of insufficient or lower-quality sleep due to adverse health conditions such as hypertension, diabetes, heart disease, and stroke. Older people account for roughly 35% of OTC medication use in the U.S., and 12% of adults 65 and older take OTC sleeping pills.
Chronically taking these medications can be problematic for elderly adults because our metabolism slows down as we age, which extends the half-life of medications and prolongs their effects. This can lead to a “residual sedative effect” if these sleep aids are taken in the evening.
Teenagers and young adults should also exercise caution with diphenhydramine. The FDA warns that higher-than-recommended doses of diphenhydramine can lead to serious medical problems , including seizures, heart attack, coma, and death. In recent years, many young people have been admitted to hospitals after consuming excessive amounts of diphenhydramine as part of the “Benadryl Challenge” promoted through social media platforms.
Doxylamine
Like diphenhydramine, doxylamine – also known as doxylamine succinate – is a first-generation antihistamine that can produce sedative effects. Doxylamine can serve as a short-term treatment for insomnia , or be used with decongestants to alleviate cold symptoms such as sneezing or nasal congestion. It is marketed under brand names such as Unisom SleepTabs, Medi-Sleep, and Good Sense Sleep Aid, and may also be an active ingredient in pain-relieving and fever-reducing medications.
If you take doxylamine for insomnia and symptoms persist longer than two weeks, you should contact your doctor about other medication options. Likewise, doxylamine for cough and cold suppression should not be taken longer than seven days if symptoms continue. To date, 31 major drug interactions with doxylamine – including aspirin and acetaminophen – have been identified.
As with diphenhydramine, studies have shown that senior citizens often take these medications chronically. This can lead to problematic health effects, especially if the individual also consumes alcohol on a regular basis.

Valerian
Valerian is an herb marketed and sold as a dietary supplement under the name “valerian root,” and is often found in mild sedatives used to treat insomnia and anxiety. While the functionality of valerian is not fully understood, researchers believe it interacts with GABA, serotonin, and adenosine receptors. Thus far, evidence that valerian is an effective treatment for insomnia has been inconclusive.
Since valerian is a dietary supplement, it is not subjected to the same level of FDA evaluation and approval as other types of sleep medication. As a result, the composition of valerian root pills may vary by brand. High doses of valerian at night have been attributed to morning sleepiness, but a standard 600mg dose does not appear to cause issues with reaction time, alertness, or concentration.
The effects of valerian on unborn fetuses and infants need to be studied further, so pregnant women or nursing mothers should not take valerian unless they are under medical supervision. The same goes for children under 3 years. Additionally, valerian may interact with other sleep medications and produce added grogginess the next day.
Do OTC Sleep Aids Cause Side Effects?
While the side effects of OTC sleep aids depend on certain factors such as dose and the person taking them, these medications are associated with the following:
OTC Sleep Medication | Potential Side Effects | Interactions with Other Medication |
---|---|---|
Melatonin | Depression, dizziness, enuresis (bedwetting), excessive daytime sleepiness, headache, and nausea | 7 moderate interactions |
Diphenhydramine | Dizziness, disturbed coordination, epigastric pain, and thickening of bronchial secretions | 28 major interactions, including acetaminophen |
Doxylamine | Dizziness, drowsiness, thickening of mucus in nose or throat, and dry mouth, throat, and nose | 31 major interactions, including acetaminophen and aspirin |
Valerian | Headache, upset stomach, cognitive dysfunction, dry mouth, feelings of excitement or unease, strange dreams, and daytime drowsiness | 3 major interactions, including sodium oxybate and buprenorphine |
Those with insomnia and other sleep issues can potentially benefit from taking one of these medications. However, as with other medications, you should exercise caution and speak with your doctor before taking any sort of OTC sleep aid. The physician will help you understand the potential side effects and drug interactions, as well as alternative treatment options that may serve you better.
Medical Disclaimer: The content on this page should not be taken as medical advice or used as a recommendation for any specific treatment or medication. Always consult your doctor before taking a new medication or changing your current treatment.
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