Melatonin Dosage Guide: What I Actually Tell My Patients About Sleep

I'm honestly frustrated. Last month alone, three patients came to my office taking 10mg of melatonin every night because "that's what the bottle said." One was groggy all morning, another had bizarre dreams, and the third—well, she'd developed tolerance and it wasn't working at all anymore. They'd all been misled by supplement marketing or social media advice that ignores basic physiology. Let's fix this.

Melatonin isn't a sleeping pill. It's a chronobiotic—a timing signal for your circadian rhythm. Your pineal gland produces about 0.1-0.3mg nightly under normal conditions.¹ Taking 10mg is like using a sledgehammer to hang a picture. The clinical picture here is more nuanced than most supplement companies want you to believe.

Quick Facts

What the Research Actually Shows

Here's where I have to push back against both mainstream dismissiveness and alternative overreach. The evidence isn't "melatonin works" or "melatonin doesn't work"—it's specific to certain situations.

A 2022 meta-analysis in Sleep Medicine Reviews (doi: 10.1016/j.smrv.2022.101718) pooled 31 randomized controlled trials with 5,847 total participants. They found melatonin reduced sleep onset latency by an average of 7.2 minutes compared to placebo (95% CI: 4.8-9.6 minutes, p<0.001).² That's modest but statistically significant. More importantly, they noted the effect was dose-independent—higher doses didn't produce better results.

Now, here's what drives me crazy: most studies use pharmacological doses (3-10mg) that don't mimic physiological levels. A 2017 study in Journal of Clinical Sleep Medicine (13(2):307-315) actually compared 0.3mg (physiological) to 3mg (pharmacological) in 24 healthy adults. Both improved sleep efficiency, but the lower dose caused less next-day grogginess and maintained normal melatonin receptor sensitivity.³

For jet lag, the Cochrane Database systematic review (doi: 10.1002/14651858.CD001520.pub4) analyzed 10 trials with 1,462 participants. Melatonin was effective for eastward travel (reducing jet lag by about 50%), with optimal timing being 2-3mg at local bedtime upon arrival.⁴

But—and this is critical—melatonin doesn't work like benzodiazepines. It won't knock you out through sheer chemical force. It's more like resetting your internal clock. I had a patient, a 52-year-old software engineer, who was taking 5mg at 11 PM but scrolling on his phone until 1 AM. The melatonin couldn't override that blue light exposure. We switched him to 0.5mg at 9:30 PM with phone away by 10 PM, and his sleep latency dropped from 90 minutes to about 20.

Dosing & Recommendations: What I Actually Prescribe

Okay, let's get practical. If you're going to use melatonin, here's exactly what I tell patients:

For sleep onset issues: Start with 0.3mg (300mcg). Yes, that's less than most products contain. Life Extension makes a 300mcg capsule that's perfect. Take it 30-60 minutes before your target bedtime. If after a week you're not seeing improvement, you can increase to 0.5mg, but I rarely go above 1mg for simple sleep onset.

For circadian rhythm disorders: This is where timing matters more than dose. For delayed sleep phase (night owls), take 0.3-0.5mg 4-5 hours before your current bedtime, then gradually move it earlier by 15 minutes every few days. A 2021 study in Sleep (44(2):zsaa161) with 307 participants found this "phase advance" protocol effective in 68% of cases.⁵

For jet lag: 2-3mg at local bedtime upon arrival for eastward travel. For westward, it's less effective, but you could try 0.5mg upon arrival.

Forms matter: Immediate-release is best for most people. Time-release formulations can be useful for middle-of-the-night awakenings, but they're trickier to dose correctly. Thorne Research makes a 1mg immediate-release that's reliable.

Here's a dosing table based on indication:

Point being: start low. Your body produces micrograms, not milligrams. The "more is better" approach backfires with hormones.

Who Should Absolutely Avoid Melatonin

This is non-negotiable. If you fall into these categories, don't take melatonin without discussing with your physician:

Autoimmune conditions: Melatonin stimulates immune function. In rheumatoid arthritis, lupus, multiple sclerosis, or other autoimmune diseases, it can potentially exacerbate symptoms. A 2019 review in Frontiers in Immunology (10:2741) detailed how melatonin modulates Th1/Th2 balance—helpful for some, harmful for autoimmune states.⁶

Pregnancy and breastfeeding: We just don't have enough safety data. Melatonin crosses the placenta and appears in breast milk. The NIH's Office of Dietary Supplements notes insufficient evidence for safety during these periods.⁷

Taking certain medications: Blood thinners (warfarin), immunosuppressants, diabetes medications, and some antidepressants can interact. Melatonin might increase bleeding risk with warfarin or enhance sedative effects of CNS depressants.

Children (except specific cases): Generally not recommended unless prescribed for ADHD-related sleep issues or autism spectrum disorders under medical supervision. Their developing endocrine systems are different.

I had a patient with Hashimoto's thyroiditis who started taking 5mg melatonin for sleep. Her thyroid antibodies jumped from 34 IU/mL to 89 IU/mL over three months. We stopped the melatonin, focused on sleep hygiene, and they dropped back to 42. Correlation isn't causation, but the timing was suspicious enough.

FAQs

Can I become dependent on melatonin?
Not in the addictive sense, but you can develop tolerance if you take high doses long-term. Your receptors downregulate. That's why I recommend cycling off after 4-8 weeks and never exceeding 1mg for routine use.

Why do I have weird dreams with melatonin?
Melatonin increases REM sleep density. For some people, that means more vivid or bizarre dreams. Usually it's dose-dependent—lower doses often reduce this effect.

Should I take it every night?
No. It's meant for short-term circadian resetting, not chronic sleep aid. After a few weeks, your body should have recalibrated. If you still need it, there might be underlying issues (sleep apnea, anxiety, poor sleep hygiene) that need addressing.

What about melatonin for COVID or other illnesses?
Some preliminary research suggested immune-modulating effects, but we lack robust clinical trials. Don't self-prescribe melatonin for COVID prevention or treatment—stick to proven interventions.

Bottom Line

Look, I know sleep struggles are real. I've had them myself during residency. But melatonin isn't a magic bullet—it's a subtle timing signal. Use it wisely, at physiological doses, and combine it with good sleep hygiene: consistent bedtime, dark/cool room, no screens before bed. That combination actually works.

If I had a dollar for every patient who came in taking melatonin wrong... well, I'd have a lot of dollars. But what I'd rather have is patients sleeping better with the right approach.