The most effective thing you can take for sleep depends on whether your problem is occasional or ongoing. For the occasional rough night, over-the-counter antihistamines or a low dose of melatonin can help. For chronic insomnia, sleep medications are less effective than behavioral therapy, and clinical guidelines from the VA and Department of Defense call cognitive behavioral therapy for insomnia (CBT-I) the gold standard treatment. Here’s what actually works, what to watch out for, and how to choose.
Melatonin: The Most Popular Supplement
Melatonin is a hormone your body already makes to signal that it’s time to sleep. Taking a supplement nudges that signal along, which is why it works best for problems with sleep timing (jet lag, shift work, a schedule that’s drifted late) rather than deep-seated insomnia. The NHS recommends 2 mg of a slow-release tablet taken one to two hours before bed for short-term sleep problems. For longer-term use, doses can gradually increase up to 10 mg, though most people do fine at the lower end.
One issue worth knowing: melatonin supplements aren’t tightly regulated for accuracy. A recent analysis of ten commercial products found that four contained melatonin levels outside the acceptable 90 to 110 percent range of what the label claimed. That means you could be getting significantly more or less than you think. Choosing a product with third-party testing (look for USP or NSF certification on the label) reduces that risk.
Over-the-Counter Antihistamines
Most OTC sleep aids at the pharmacy contain one of two older antihistamines: diphenhydramine (the active ingredient in Benadryl and ZzzQuil) or doxylamine (found in Unisom SleepTabs). Both cause drowsiness as a side effect, which is why they got repurposed as sleep aids. They can work for the occasional sleepless night, but they come with real downsides.
Your body builds tolerance to these antihistamines quickly. The more often you take them, the less likely they are to make you sleepy. Side effects include next-day grogginess, dry mouth, dizziness, nausea, and problems with balance and coordination. Hopkins Medicine and the Mayo Clinic both recommend against regular use. Think of them as a one-off tool, not a nightly habit.
L-Theanine and Other Calming Supplements
L-theanine is an amino acid found naturally in green tea. It doesn’t knock you out the way an antihistamine does. Instead, it promotes relaxation without heavy sedation, which can make it easier to fall asleep if anxiety or a racing mind is keeping you up. A typical dose is 200 mg taken up to two hours before bed, and some people combine it with a low dose of melatonin for a stronger effect. The effective range in studies runs from 100 to 400 mg.
Magnesium glycinate is another popular option. It plays a role in nervous system regulation, and many people who sleep poorly turn out to be mildly deficient. Glycine, the amino acid it’s paired with, has its own mild calming properties. Neither L-theanine nor magnesium will produce dramatic results on their own, but they carry very few side effects and can be part of a broader sleep routine.
Tart Cherry Juice
Tart cherry juice, specifically from Montmorency cherries, contains naturally occurring melatonin at levels more than six times higher than other tart cherry varieties. Small studies have shown improved sleep duration and quality after drinking concentrated tart cherry juice for about a week, particularly in people with insomnia. The research is still limited, and no one has pinned down exactly how much juice you need. But if you prefer a food-based approach over pills, it’s a reasonable option to try.
Prescription Sleep Medications
If over-the-counter options aren’t cutting it, prescription medications fall into two main categories. Z-drugs like zolpidem and zaleplon are short-acting, with half-lives of just one to two hours, meaning they help you fall asleep but wear off quickly. Eszopiclone lasts longer, with a half-life of six to nine hours, which helps more with staying asleep through the night. All of these carry concerns about cognitive decline with use beyond a few months, and there are reports of unusual nighttime behaviors like sleepwalking.
Benzodiazepines are the older class of prescription sleep aid. They’re effective but come with a high rate of rebound insomnia (your sleep gets worse when you stop), memory problems, fall risk in older adults, and the potential for tolerance and dependence with long-term use. They also interact dangerously with opioids and other sedating medications. For these reasons, most current guidelines steer clinicians toward other options first.
Why Behavioral Therapy Outperforms Medication
If your sleep problems have lasted more than a few weeks, the single most effective treatment isn’t something you take. CBT-I, or cognitive behavioral therapy for insomnia, is a structured program that typically runs four to eight sessions. It retrains the habits and thought patterns that keep insomnia going: spending too long in bed, associating the bedroom with frustration, irregular sleep timing, and the anxiety about sleep itself that makes everything worse.
The 2025 VA/DoD clinical practice guideline is blunt about the comparison: sleep medications treat symptoms, while behavioral therapies target the underlying cause. Medications haven’t been found as effective as behavioral therapies for chronic insomnia, and CBT-I provides longer-lasting benefits with fewer side effects. A shorter version called BBT-I (brief behavioral therapy for insomnia) is recommended when full CBT-I isn’t available quickly. You can access CBT-I through a therapist, through VA programs, or through apps like the VA’s own CBT-I Coach.
One important note from the same guidelines: sleep hygiene alone (keeping a cool room, avoiding screens, cutting caffeine) is not considered an adequate standalone treatment for chronic insomnia. Those habits matter, but they’re the foundation, not the fix.
Choosing What’s Right for You
For a single bad night or jet lag, melatonin at 2 to 3 mg taken one to two hours before bed is the simplest starting point. An OTC antihistamine can work in a pinch but shouldn’t become routine. If stress or a busy mind is the main barrier, L-theanine at 200 mg is a low-risk option worth trying.
If you’ve been struggling for weeks, the pattern matters more than the pill. Prescription medications can bridge a rough period, but they lose effectiveness over time and carry real risks. CBT-I is the approach with the strongest evidence for lasting improvement, and it works even for people who have had insomnia for years.