Key takeaways:
For occasional insomnia, over-the-counter (OTC) sleep aids may help you fall asleep faster and stay asleep longer.
Even common OTC sleep aids can come with possible side effects and risks. They may not be right for everyone.
For chronic insomnia, cognitive behavioral therapy works better than OTC sleep aids.
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We all have nights when it’s hard to fall asleep or stay asleep. Insomnia is common, and only about half of us feel well rested when we get up each day.
For frequent insomnia, experts recommend checking for underlying sleep disorders. They also recommend treating with cognitive behavioral therapy for insomnia (CBT-I) first. But for jet lag, or occasional trouble with sleep, some over-the-counter (OTC) sleep aids might provide relief. Here, we look into four OTC sleep aids, their typical dosage, side effects, and some things to keep in mind.
1. Diphenhydramine
Diphenhydramine (Benadryl) is a common ingredient in OTC sleep aids. It’s an antihistamine that treats allergy symptoms, like sneezing or itching. One of the main side effects of diphenhydramine is sleepiness. Because of this, it can sometimes help with short-term sleep problems.
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Diphenhydramine is available OTC in many different dosage forms, including:
Tablet
Capsule
Oral liquid
Chewable tablet
Fast-dissolving tablet
For allergies, it’s sold under the brand name Benadryl. But it’s also in sleep formulations like Unisom SleepMelts and ZzzQuil. And in combination medications for pain such as Aleve PM, Advil PM, and Tylenol PM.
Typical dosage
Diphenhydramine can be taken for short periods of time to help with sleep. The typical dosage is 25 mg to 50 mg taken 30 minutes before bedtime.
Side effects
Common side effects of diphenhydramine include:
Dry mouth, throat, and nasal passages
Mild weakness, dizziness, or clumsiness
Sleepiness
Constipation
Thicker mucus or phlegm
More serious side effects, though less common, may include:
Vision problems
Trouble with urination
Heart rhythm problems
Confusion
Hallucinations
Falls from weakness or dizziness
Wheezing and trouble breathing
Warnings
Most people can take an OTC sleep aid like diphenhydramine for occasional sleep problems. But it’s not right for everyone. People who should avoid taking diphenhydramine for occasional sleep issues include:
People who are breastfeeding
Children younger than 2 years
Children of any age taking diphenhydramine as a sleep aid instead of an allergy medication
Older adults and people at a higher risk of confusion and falls
People with heart problems
People with asthma
Men with an enlarged prostate
Glaucoma
People who are driving or operating heavy equipment
Taking diphenhydramine with alcohol, opioids, benzodiazepines, or other sleeping pills can be dangerous.
Antihistamines like diphenhydramine may also increase the risk of dementia. This risk increases with higher doses and over longer periods of time.
2. Doxylamine
Doxylamine (Unisom) is an antihistamine like diphenhydramine. It’s also used in sleep aid formulations.
Doxylamine is available OTC as a tablet or capsule, oral liquid, and chewable tablet. For sleep, it’s sold under the brand Unisom SleepTabs. Remember to check the label since not all Unisom products contain doxylamine. It’s also in some combination cold and flu products like Vicks NyQuil Cold & Flu Relief.
Typical dosage
Doxylamine comes in 25 mg tablets or capsules. The typical dosage for sleep is 1 or 2 tablets 30 minutes before bed. Doxylamine is approved for occasional insomnia in adults and children 12 years and older.
Side effects
Doxylamine and diphenhydramine have many of the same side effects. One difference is that doxylamine stays in your body longer than diphenhydramine. So you might be more likely to feel groggy the next day.
Some common side effects of doxylamine include:
Sleepiness and drowsiness
Mild dizziness, weakness, or lack of coordination
Thicker mucus and phlegm
Dry mouth and throat
Constipation
Headache or trouble concentrating
More serious side effects may include:
Trouble urinating
Vision problems
Hallucinations
Wheezing or trouble breathing
Heart rhythm problems
Confusion
Falling from weakness or dizziness
Warnings
Like diphenhydramine, most people can take doxylamine for occasional sleep problems. But people who should avoid it include:
Children younger than 2 years
Older adults
People with heart problems or asthma
Men with an enlarged prostate
Those with glaucoma
Don’t take doxylamine before you drive or operate equipment. Combining it with alcohol or other sedating medications could be dangerous. It also may increase the risk of dementia at higher doses or taking it for a long time.
3. Melatonin
Melatonin is a hormone that your body produces to help regulate your sleep and wake cycles. OTC melatonin is a synthetic version. Melatonin products may be helpful for people who:
Are experiencing jet lag
Do shift work
Have trouble falling asleep at a typical time (delayed sleep-wake disorder)
There’s not enough evidence that it helps with insomnia on a long-term basis. And because it’s considered a supplement, the dose and quality aren’t regulated by the FDA.
Melatonin is available OTC in many different dosage forms, including:
Tablet
Fast-dissolving tablet
Powder for dissolving in liquid
Oral liquid
Gummies
Cream
Gel
Transdermal patch
You can find melatonin on its own and in products like Emergen-Zzzz Nighttime Sleep Aid.
Typical dosage
A typical melatonin dosage for adults is 3 mg to 5 mg an hour or two before bedtime. It’s a good idea to start at a lower dose, like 1 mg or 2 mg, and increase slowly as needed. Doses over 8 mg are more likely to cause side effects.
For kids and teens, start with 0.5 mg and increase slowly as needed. The highest recommended dose varies by age:
Age 4 to 5 years: 1 mg to 2 mg before bed
Age 6 to 12 years: 2 mg to 3 mg
Teens: Up to 5 mg
Side effects
The risk of melatonin side effects increases with doses over 8 mg to 10 mg. Side effects may include:
Sleep disturbances like nightmares
Sleepiness the following day
Nausea
Headache
Depression
Dizziness
Warnings
Short-term melatonin use for sleep is probably safe for most people. But some could be at higher risk of side effects. Talk with your healthcare team before taking melatonin if:
You take medication for seizures.
You take blood thinners.
You are pregnant or breastfeeding.
You’re considering it for children, especially under 5 years old.
Older adults, especially those with dementia, should also talk with a healthcare professional before taking melatonin.
4. Cannabidiol (CBD)
You may find cannabidiol (CBD) in some OTC sleep aids. CBD comes from the cannabis sativa plant. It can be taken orally, applied topically, or inhaled.
CBD doesn’t give most people the feeling of being “high” like THC — another chemical derived from the same plant. But some studies suggest that CBD might help with sleep. Other studies find no difference between CBD and a placebo.
It could be that CBD helps pain and anxiety, and that makes people feel like they’re sleeping better. But sleep tests show that the quality of sleep may be the same or worse. Since CBD is a newer treatment for sleep problems, more research is needed to see if it’s an effective sleep aid.
CBD products aren’t approved by the FDA. And they’re not legal in every state. Some companies market them as unapproved treatments for certain conditions. So, you’ll want to talk with your healthcare team before giving these products a try.
Typical dosage
The few studies looking at CBD for sleep used doses from 18 mg to 800 mg. Most effects on sleep happened around 150 mg. Many OTC products contain 10 mg to 50 mg of CBD. Experts recommend no more than 100 mg per day for healthy adults. If you decide to try CBD for sleep, start at a low dose before bed and increase slowly.
Side effects
At typical doses, side effects of CBD may include:
Stomach upset
Sleepiness
Lower appetite
Changes in liver tests
Fatigue
Dizziness
Headache
Nausea
Diarrhea
Warnings
The following considerations are important to keep in mind if you’re considering CBD for sleep:
It’s not legal in every state.
Don’t use it with alcohol or medications that cause sedation.
It may cause or worsen effects on the liver.
Older adults may be at a higher risk of falls and side effects with CBD.
CBD isn’t recommended during pregnancy and breastfeeding.
Children and young adults may have a higher risk of side effects that involve focus, thinking, and brain development.
Do OTC sleep aids work?
When it comes to research on the best OTC sleep aids, the evidence is mixed. Studies have found that:
Diphenhydramine shortened the amount of time it took to fall asleep by an average of 8 minutes. And people stayed asleep for an average of 12 minutes longer than people taking a placebo pill. But they had no improvement in the quality of sleep compared with placebo.
Melatonin shortened the time it took to fall asleep by about 9 minutes. There was a small improvement in the quality of sleep compared with placebo.
Doxylamine hasn’t been studied as much as diphenhydramine for sleep. But specific formulations, like Unisom, are approved by the FDA as a nighttime sleep aid.
CBD studies have mixed results when it comes to sleep. Low-dose CBD-only products like those marketed for sleep might not make much of a difference. But they might help with pain or anxiety. Other products that contain a combination of CBD and THC might help people fall asleep, but over time can actually worsen the quality of sleep.
OTC sleep aids aren’t recommended for chronic insomnia. The American Academy of Sleep Medicine (AASM), the American Academy of Family Physicians (AAFP), and other professional organizations recommend cognitive behavioral therapy (CBT) for chronic or frequent insomnia. If you need more help with sleep, your healthcare team may recommend a prescription medication for insomnia.
When would a prescription sleep aid be recommended?
Times of stress, sickness, and travel can affect your sleep. Even though OTC sleep aids are easily accessible, it doesn’t mean they should be taken on a regular basis.
If you experience trouble sleeping for longer than a few weeks, talk with your healthcare team. You may have an underlying health condition or sleep disorder. And there are more effective and safer treatments for chronic insomnia.
You should also speak with a healthcare professional if you’ve been taking:
Diphenhydramine or doxylamine for 2 weeks or more
Melatonin products for more than 6 months for adults (3 months for children)
CBD to help with sleep. There’s not much information about how long it’s safe to take it.
Frequently asked questions
A calming and regular sleep routine is helpful for people with dementia. Avoid antihistamines and sedating medications in older adults at higher risk of falls. If sleep aids are needed for older adults, experts recommend prescription medications like low-dose doxepin, ramelteon, or suvorexant.
There aren’t any OTC sleeping pills that are considered safe to take daily in the long term. And prescription sleep aids are also used only under the guidance of your healthcare team.
The most effective natural sleep aid is cognitive behavioral therapy for insomnia (CBT-I). Regular sleep habits and practices are helpful, too. There isn’t a lot of evidence for other natural remedies like supplements. But some natural sleep aids that may help include magnesium, L-tryptophan, L-theanine, chamomile, and valerian.
A calming and regular sleep routine is helpful for people with dementia. Avoid antihistamines and sedating medications in older adults at higher risk of falls. If sleep aids are needed for older adults, experts recommend prescription medications like low-dose doxepin, ramelteon, or suvorexant.
There aren’t any OTC sleeping pills that are considered safe to take daily in the long term. And prescription sleep aids are also used only under the guidance of your healthcare team.
The most effective natural sleep aid is cognitive behavioral therapy for insomnia (CBT-I). Regular sleep habits and practices are helpful, too. There isn’t a lot of evidence for other natural remedies like supplements. But some natural sleep aids that may help include magnesium, L-tryptophan, L-theanine, chamomile, and valerian.
The bottom line
Over-the-counter (OTC) sleep aids may help short-term sleep problems for some people. But they can cause side effects and interact with other medications. Ask your healthcare team if it’s safe to take them with your current medications and health conditions. And if you’re using OTC sleep aids for longer periods of time, it could be a sign of an underlying health issue.
Why trust our experts?
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