A low dose of melatonin, taken 1 to 2 hours before bed, is the most common and well-supported starting point when you can’t sleep. But melatonin isn’t the only option, and it’s not always the best one depending on why you’re awake. What works for occasional restlessness differs from what helps with chronic insomnia, and some popular choices come with real trade-offs worth knowing about.
Melatonin: The Go-To Starting Point
Melatonin is a hormone your brain naturally produces as it gets dark, signaling your body to wind down. Supplemental melatonin doesn’t knock you out the way a sedative does. Instead, it nudges your internal clock toward sleep, which makes it most useful when your sleep timing is off rather than when anxiety or pain is keeping you awake.
The NHS recommends a 2 mg slow-release tablet taken 1 to 2 hours before bedtime for short-term insomnia. For ongoing sleep problems, the same 2 mg dose taken 30 minutes to 1 hour before bed is the usual starting point. Many supplements sold in the U.S. contain 5 or 10 mg, which is far more than most people need. Starting low, around 1 to 3 mg, tends to work better and causes fewer side effects like grogginess the next morning.
One important caution: don’t mix melatonin with alcohol. Both slow down your central nervous system, and combining them can cause excessive drowsiness, impaired breathing during sleep, dizziness, and disorientation. A documented case report described a person who experienced rapid heartbeat, hallucinations, flushed skin, and shaking after taking both in the same evening. If you have any liver issues, melatonin may also put extra strain on liver function.
Magnesium Supplements
Magnesium plays a role in muscle relaxation and nervous system regulation, which is why it shows up in nearly every “natural sleep aid” list. The reality is a bit more nuanced than the marketing suggests. Most of the clinical research supporting magnesium for sleep has actually used magnesium oxide, not the glycinate form that’s become trendy. One recent study of magnesium glycinate (providing 250 mg of elemental magnesium plus 1,523 mg of glycine) showed modest benefits for adults with sleep trouble, but the evidence is still thin.
Magnesium citrate performed even less impressively. In one study, people taking magnesium citrate reported similar sleep improvements to those taking a placebo, meaning both groups slept about the same. If you want to try magnesium for sleep, magnesium oxide has the most research behind it. It’s also the cheapest form. Taking it about 30 minutes before bed is typical. Most people tolerate it well, though higher doses can cause loose stools.
Tart Cherry Juice
This one sounds like a folk remedy, but there’s a biological basis for it. Tart cherries, specifically the Montmorency variety, contain small amounts of naturally occurring melatonin along with compounds that reduce inflammation. A pilot study published in the American Journal of Therapeutics found that drinking roughly 8 ounces of tart cherry juice twice a day improved both sleep duration and quality in older adults with insomnia. It’s not a powerful effect, but for people who prefer food-based approaches or want to avoid pills, it’s a reasonable option to try alongside other habits.
Over-the-Counter Antihistamines
The active ingredients in most OTC sleep aids sold at pharmacies are antihistamines: diphenhydramine (the ingredient in Benadryl and ZzzQuil) and doxylamine (the ingredient in Unisom SleepTabs). These block histamine receptors in the brain, which causes drowsiness as a side effect.
They work, but they come with significant downsides. Next-day grogginess is common. Your body builds tolerance quickly, meaning they stop working as well after several consecutive nights. Cleveland Clinic physicians recommend these only for occasional sleeplessness, not as a nightly routine. They’re a reasonable choice if you have one rough night and need to reset, but they shouldn’t become a habit.
Adults over 65 should generally avoid antihistamines for sleep entirely. These medications have strong anticholinergic effects, which means they interfere with a key brain chemical involved in memory and alertness. In older adults, this translates to increased risk of falls, confusion, and cognitive problems. The American Geriatrics Society’s Beers Criteria, a widely used safety reference, lists diphenhydramine as a medication to avoid in this age group.
Prescription Sleep Medications
If over-the-counter options aren’t cutting it after a few weeks, prescription medications are the next step. The newest class works by blocking wake-promoting signals in the brain rather than sedating you into sleep. Your brain produces chemicals called orexins that keep you alert and awake. These newer medications block those orexin receptors, essentially turning down the “stay awake” signal so sleep can happen naturally. Three are currently FDA-approved: suvorexant (Belsomra), lemborexant (Dayvigo), and daridorexant (Quviviq).
Older prescription options include benzodiazepines and a class sometimes called Z-drugs. Both carry risks of next-day impairment. The FDA specifically warns that all insomnia medications can affect your ability to drive and perform tasks requiring alertness the following morning. For older adults, benzodiazepines and Z-drugs are on the Beers Criteria avoidance list because they increase the risk of cognitive problems, delirium, falls, and fractures. Longer-acting versions are particularly concerning because they metabolize slowly and can accumulate to problematic levels.
What Matters Beyond What You Take
No supplement or medication works well if the basics are working against you. A cool, dark room (around 65 to 68°F) makes a measurable difference in how quickly you fall asleep. Screens within an hour of bedtime suppress your natural melatonin production, which is ironic if you’re then taking a melatonin pill to compensate. Caffeine has a half-life of about 5 to 6 hours, meaning half the caffeine from a 2 p.m. coffee is still circulating at 7 or 8 p.m.
Alcohol deserves special mention because many people use it as a sleep aid. While it does make you fall asleep faster, it fragments sleep in the second half of the night and suppresses REM sleep, the stage most important for memory and emotional regulation. Combining alcohol with any sleep aid, whether melatonin, antihistamines, or prescriptions, amplifies sedation and can impair breathing during sleep. This is especially dangerous for anyone with sleep apnea, since alcohol further relaxes the airway muscles that are already prone to collapse.
If you’ve been unable to sleep for more than a few weeks and nothing over the counter is helping, the problem may not be what you’re taking but what’s driving the wakefulness. Anxiety, sleep apnea, chronic pain, and hormonal changes all cause insomnia that no supplement will fix on its own. Cognitive behavioral therapy for insomnia (CBT-I) is considered the first-line treatment for chronic insomnia and has better long-term outcomes than any medication, with effects that last after you stop the program rather than disappearing when you stop a pill.