Several drugs can make you sleep, ranging from antihistamines you can buy at any pharmacy to prescription medications that work on specific brain pathways. The right choice depends on whether you struggle to fall asleep, stay asleep, or both. Here’s how each category works and what to expect from it.
Over-the-Counter Antihistamines
The two most common drugstore sleep aids are diphenhydramine (the active ingredient in Benadryl and ZzzQuil) and doxylamine (found in Unisom SleepTabs). Both are first-generation antihistamines that block histamine receptors in the brain, producing drowsiness as a side effect. They aren’t designed specifically for sleep, but they’re widely used for it.
Doxylamine reaches peak blood levels in about 1.5 to 2 hours, with a recommended dose of 25 mg taken 30 minutes before bed. Its half-life is roughly 12 hours, which means a significant amount of the drug is still active in your system when you wake up. That long half-life is the main drawback: many people experience next-day grogginess, sluggishness, or a “hangover” feeling. If that happens, dropping to 12.5 mg or taking the dose earlier in the evening can help. Diphenhydramine has a similar profile, with drowsiness that can linger into the morning.
Neither drug is meant for long-term use. Your body builds tolerance to antihistamines quickly, sometimes within a few days, making them less effective the longer you take them.
Melatonin and Melatonin-Based Options
Melatonin is a hormone your brain naturally produces as darkness falls, signaling that it’s time to sleep. Supplemental melatonin, available without a prescription, works best for people whose internal clock is off, such as those with delayed sleep schedules or jet lag. It reduces the time it takes to fall asleep by roughly 20 to 60 minutes in people with a genuinely shifted sleep-wake cycle, but it’s less effective for general insomnia.
The best approach is to start with a low dose (1 mg) and increase by 1 mg per week until you find what works. Most studies use 3 to 6 mg per day. Immediate-release melatonin is better for falling asleep, while slow-release formulations help more with staying asleep through the night. Taking it 30 to 60 minutes before your target bedtime gives it time to work.
Prescription melatonin receptor agonists like ramelteon target the same receptors but with greater precision. Ramelteon is specifically recommended for sleep-onset insomnia and, unlike most prescription sleep drugs, carries no risk of physical dependence. Another prescription option, tasimelteon, is used primarily for people who are totally blind and have a free-running circadian rhythm that doesn’t sync to the 24-hour day.
Z-Drugs: Zolpidem, Eszopiclone, and Zaleplon
The so-called Z-drugs are the most commonly prescribed sleeping pills. They enhance the activity of GABA, the brain’s main calming neurotransmitter, making you fall and stay asleep. They work on a narrower set of brain receptors than older sedatives, which is why they tend to produce fewer side effects, though they still carry real risks.
The three Z-drugs differ mainly in how long they last. Zaleplon (Sonata) has a half-life of about 1 hour, making it useful if you wake up in the middle of the night and need help falling back asleep without morning impairment. Zolpidem (Ambien) has a half-life of 2 to 3 hours and is used for both falling asleep and staying asleep. Eszopiclone (Lunesta) lasts the longest and is recommended for both sleep onset and sleep maintenance.
All three carry an FDA boxed warning for complex sleep behaviors, including sleepwalking, sleep-driving, and performing activities while not fully awake. These events have resulted in serious injuries and deaths. If you’ve ever experienced a complex sleep behavior episode on one of these drugs, you should not take it again. The American Academy of Sleep Medicine gives all three a “weak” recommendation, meaning they can help but should generally be tried after behavioral approaches like cognitive behavioral therapy for insomnia (CBT-I) have been attempted.
Orexin Receptor Antagonists
This is the newest class of prescription sleep medication, and it works through a fundamentally different mechanism. Instead of sedating the brain, these drugs block orexin, a chemical that promotes wakefulness. The result is more like turning off the “wake” signal than forcing the brain into sleep.
Three are currently available: suvorexant (Belsomra), lemborexant (Dayvigo), and daridorexant (Quviviq). Their major advantage over Z-drugs and benzodiazepines is safety: they are not associated with physical tolerance, withdrawal symptoms, or rebound insomnia when stopped. They also don’t disrupt normal sleep architecture, meaning the balance of light sleep, deep sleep, and REM sleep stays intact. For sleep maintenance insomnia specifically, the American Academy of Sleep Medicine recommends suvorexant as one treatment option.
Benzodiazepines
Benzodiazepines like temazepam and triazolam were once the go-to prescription for insomnia. They enhance GABA activity broadly across the brain, producing strong sedation along with muscle relaxation and anti-anxiety effects. The problem is dependence: roughly half of people who use benzodiazepines for more than one month develop physical dependence on them. Most guidelines now recommend limiting their use to days or 1 to 2 weeks at most, and no longer than 2 to 4 weeks.
Temazepam is typically prescribed at 15 to 30 mg at bedtime for short-term use. These drugs are generally reserved for acute insomnia that’s severe or causes significant distress, particularly when rapid relief is needed. They are not considered appropriate for chronic, ongoing sleep problems.
Off-Label Medications
Several drugs prescribed primarily for depression or other psychiatric conditions cause significant drowsiness, and doctors frequently prescribe them at low doses for sleep. Trazodone is the most common, often used at around 50 to 100 mg at bedtime (well below the doses used for depression). It works partly by blocking serotonin and histamine receptors, which produces sedation.
Quetiapine, an antipsychotic, is another off-label option, typically at low doses around 25 to 100 mg for sleep. It causes drowsiness through its effects on histamine and other receptor systems. Neither trazodone nor quetiapine is FDA-approved for insomnia, and they come with their own side-effect profiles, including potential weight gain, dizziness, and daytime sedation. They’re most often used when someone has both insomnia and another condition (like depression or anxiety) that the same medication can address.
How These Options Compare in Practice
The choice between sleep medications comes down to the specific sleep problem you’re dealing with:
- Trouble falling asleep only: Melatonin, ramelteon, zaleplon, or zolpidem are typical starting points, depending on severity.
- Trouble staying asleep: Suvorexant, eszopiclone, or low-dose doxepin (a prescription antihistamine) target sleep maintenance.
- Both falling and staying asleep: Eszopiclone, zolpidem extended-release, or orexin receptor antagonists cover both problems.
- Shifted sleep schedule: Melatonin or ramelteon helps reset circadian timing rather than forcing sedation.
The American Academy of Sleep Medicine considers cognitive behavioral therapy for insomnia the primary treatment for chronic sleep problems, with medications recommended mainly for people who don’t respond to behavioral strategies or need short-term relief while working on them. All current pharmacological recommendations for chronic insomnia carry a “weak” strength rating, reflecting the reality that no sleep drug is a perfect long-term solution. The best outcomes typically combine a medication with changes in sleep habits and behavior.