5-HTP vs Melatonin for Sleep: Which Should You Take?

Melatonin is the pick for most people: two meta-analyses, a Cochrane review, and dose-finding trials at 0.3 to 1 mg. 5-HTP has two small human sleep trials and an interaction warning that applies to anyone on an antidepressant, a triptan, or tramadol. Choose 5-HTP only when a clinician has suggested a serotonin precursor and you take nothing serotonergic.

The verdict

For most people: melatonin, 0.5 to 1 mg, 30 to 60 minutes before bed. It has the trials.

When 5-HTP wins: a clinician has suggested a serotonin precursor and you take nothing that acts on serotonin. The one modern trial used 100 mg a day for 12 weeks.

The fact that decides it: melatonin is a timing signal your brain already makes every night; 5-HTP is raw material for serotonin, backed by two small sleep trials with 48 people between them.

One warning first, for one side only. 5-HTP raises serotonin throughout the body, not just in the brain. If you take an SSRI or SNRI antidepressant, an MAOI, a triptan for migraine, tramadol, or St. John's wort, adding 5-HTP stacks a second serotonin booster on the first, and too much serotonin produces serotonin syndrome: agitation, a racing heart, sweating, twitching muscles, fever, and sometimes a hospital bed. The pharmacology review of 5-HTP names serotonin syndrome as one of its two main safety concerns (Turner 2005, Pharmacology and Therapeutics), and a 2011 case report describes a man on an MAOI who added over-the-counter 5-HTP and developed mania with no prior history of it (Pardo 2011, General Hospital Psychiatry). Melatonin has no equivalent interaction class. If any of those medications is in your cabinet, the comparison is over: ask the prescriber before touching 5-HTP.

Side-by-side

Where they actually differ

Melatonin is a message. 5-HTP is a shipment of parts. That is the whole difference, and it explains everything else here.

Your pineal gland releases melatonin when the light goes down, light at night blocks it, and its job is to set the timing of your 24-hour clock (NCCIH). A supplement adds to a signal the brain is already sending, and it arrives fast and leaves fast: roughly 15 percent of a swallowed dose reaches the blood, the peak comes about 50 minutes later, and the half-life is about 45 minutes (Harpsøe 2015, European Journal of Clinical Pharmacology). At 0.3 mg that pulse mimics a normal night. At 3 mg in adults over 50, blood melatonin was still elevated in daylight (Zhdanova 2001).

5-HTP, short for 5-hydroxytryptophan, is the step between the amino acid tryptophan and serotonin. The enzyme that converts it, aromatic L-amino acid decarboxylase, works throughout the body, so a share of every capsule becomes serotonin in the periphery, where it cannot cross into the brain, and how much reaches the brain depends on how much is converted on the way. That is why medical use has paired 5-HTP with carbidopa, which blocks the peripheral enzyme (Turner 2005).

The label logic runs: 5-HTP makes serotonin, serotonin makes melatonin, so 5-HTP helps sleep. The chemistry is right. The physiology is less cooperative. Melatonin production happens in the pineal gland on a darkness-driven schedule, and the trial record does not show that more precursor means more nighttime melatonin. The one modern 5-HTP sleep trial tracked urinary melatonin; its abstract reports a rise in blood serotonin and says nothing about melatonin (Sutanto 2024).

Timescale follows. Melatonin works the night you take it. 5-HTP, in the trial that tested it alone, separated from the control group at week 12. If you want to know in three nights whether something is helping, only one of these two can tell you.

What the trials say

No trial has put 5-HTP and melatonin head to head for sleep. We searched PubMed for one on October 14, 2026 and found nothing, so this compares two very different bodies of evidence.

Melatonin

The largest pooled analysis covered 19 randomized, placebo-controlled trials and 1,683 adults and children with primary sleep disorders: melatonin shortened time to fall asleep by 7.06 minutes (95 percent confidence interval 4.37 to 9.75), lengthened total sleep by 8.25 minutes, and improved rated sleep quality (standardized effect 0.22), effects that were modest, did not fade over time, and were smaller than prescription hypnotics produce (Ferracioli-Oda 2013, PLoS One). An earlier meta-analysis of 17 studies and 284 subjects found the same direction: sleep onset 4 minutes faster, sleep efficiency up 2.2 points, total sleep up 12.8 minutes (Brzezinski 2005, Sleep Medicine Reviews). Grade for falling asleep: Strong. Ten minutes is real. It is not a sedative.

Dose comes from two MIT sleep-lab trials. Healthy volunteers who took 0.3 or 1 mg at 6, 8, or 9 PM fell asleep faster on polysomnography (sleep-lab recording) at either dose and any hour, with no REM suppression and no hangover (Zhdanova 1995, Clinical Pharmacology and Therapeutics). Then 30 adults over 50 took placebo, 0.1, 0.3, or 3 mg for a week each: 0.3 mg restored sleep efficiency in the 15 poor sleepers, mainly in the middle third of the night, while 3 mg also helped but caused hypothermia and left melatonin elevated into daylight. The 15 normal sleepers got nothing from any dose (Zhdanova 2001, Journal of Clinical Endocrinology and Metabolism). The limitation: 30 people, one week per dose.

For jet lag, the Cochrane review of ten trials found melatonin at destination bedtime reduced jet lag across five or more time zones in nine of them; 0.5 to 5 mg worked about equally, more than 5 mg added nothing, and 2 mg slow-release was relatively ineffective because the clock wants a short, higher peak (Herxheimer and Petrie 2002, Cochrane). Grade: Strong.

For staying asleep, the data is for a different form. In 791 adults aged 18 to 80 with primary insomnia, 2 mg prolonged-release melatonin two hours before bed cut diary sleep latency by 15.4 minutes against 5.5 on placebo in the 55 to 80 group, held for six months, and produced no tolerance, withdrawal, or rebound; the full 18 to 80 group, which included younger adults, did not reach significance on that primary measure (Wade 2010, Current Medical Research and Opinion). Grade for staying asleep, adults 55 and over: Moderate.

5-HTP

Set aside disease-specific studies and the human sleep evidence for 5-HTP is two trials.

The modern one: 30 adults in Singapore, mean age 66, took 100 mg of 5-HTP daily or nothing for 12 weeks, single-blinded, with sleep scored every four weeks by questionnaire (the PSQI) and an actigraphy watch. Blood serotonin rose. At week 12, participants who started as poor sleepers (PSQI above 5) improved their global sleep score; good sleepers did not (Sutanto 2024, Clinical Nutrition). No placebo, single blinding, 30 people, and a benefit confined to a subgroup. Grade: Preliminary.

The older one: 18 patients with sleep disorders were randomized to placebo or Gabadone, an amino acid blend containing both GABA (gamma-aminobutyric acid) and 5-HTP. The nine on the blend fell asleep in 19.1 minutes instead of 32.3 and slept 6.8 hours instead of 5.0; the nine on placebo did not change (Shell 2010, American Journal of Therapeutics). Nine per arm, a blend that cannot tell you which ingredient did the work, and a lead author listed at Targeted Medical Pharma, Inc. It is cited on many 5-HTP labels and should not be read as a 5-HTP trial.

Where 5-HTP has been studied harder is mood. The Cochrane review of tryptophan and 5-HTP for depression located 108 trials and found only two, with 64 patients between them, good enough to include; those two favored the supplements over placebo, but the reviewers called the evidence insufficient to be conclusive and noted that a possible link to eosinophilia-myalgia syndrome had not been resolved (Shaw 2002, Cochrane). 106 of 108 trials failing a quality screen tells you how the older 5-HTP literature was built.

What has not been tested

For 5-HTP: a placebo-controlled trial of 5-HTP alone for sleep in healthy adults, any sleep-maintenance outcome, any dose-finding study, and safety beyond a few months. For melatonin: nightly use for years and use in pregnancy. Melatonin's missing data is about duration. 5-HTP's is about whether it works for sleep at all.

The 5-HTP contamination history

In 1989 an outbreak of eosinophilia-myalgia syndrome (EMS, severe muscle pain plus high eosinophil counts) was traced to contaminated L-tryptophan from one manufacturer, and 5-HTP replaced tryptophan on US shelves. In 1994, FDA scientists described a family who fell ill after taking 5-HTP: one member developed EMS, two developed eosinophilia, their lot contained an impurity absent from other patients' samples, and the eosinophilia resolved after they switched to 5-HTP without it (Michelson 1994, Journal of Rheumatology). Mayo Clinic chemists later identified the contaminant, nicknamed Peak X, as 4,5-tryptophan-dione and found it in all six over-the-counter 5-HTP products they tested, at 0.5 to 10.3 percent of the case-implicated amount (Klarskov 2003, Journal of Rheumatology). A 2004 review pushed back, arguing the quantities were trivial and that two decades of worldwide use had produced no definitive toxicity case; its lead author worked at a commercial laboratory (Das 2004, Toxicology Letters).

The buyer's lesson is narrow: with 5-HTP, whether the capsule contains what the label says and nothing else is a lot-level testing question. How identity, potency, and purity testing works and what a certificate of analysis should show you matter more here than for most supplements.

Who should pick which

Before either one, fix the inputs: the sleep habits that move the needle do more than any capsule on this page. Then:

If you want the longest trial record

Melatonin, 0.5 to 1 mg, 30 to 60 minutes before bed. Two meta-analyses and a Cochrane review against two small trials is not a close call.

If you take an antidepressant, a triptan, tramadol, or St. John's wort

Melatonin, after a word with whoever prescribes. 5-HTP is off the table without that conversation.

If you fall asleep fine but wake at 2 or 3 AM, and you are 55 or older

Prolonged-release melatonin, 2 mg, about two hours before bed. That form and age group have six months of controlled data. 5-HTP has no sleep-maintenance data.

If you are flying across five or more time zones

Melatonin, 0.5 to 5 mg, at the destination's bedtime from the first night, and not the slow-release form. 5-HTP has never been tested for jet lag.

If a clinician has suggested a serotonin precursor and you take nothing that acts on serotonin

5-HTP, 100 mg once a day, from a maker who publishes a lot-specific certificate of analysis, for 12 weeks before you judge it. Expect more if you start as a poor sleeper. This is the one situation where 5-HTP is the answer.

If stress rather than timing keeps you up, neither is the first tool. Start with ten ways to encourage your body to relax, then what the ashwagandha trials actually show, which magnesium form and dose to use, and which supplements people reach for when stress runs the day.

Cost per effective day

Cost only means something at the studied dose, so the table prices each ingredient there. The three products are ours, which is why we can show the math on them rather than guess at someone else's bottle; prices were checked on the live product pages on October 14, 2026.

The math is the price divided by 60; two dots is 53 cents. Two notes. The dot is the only unit here that lets you take the 0.3 to 1 mg the sleep-lab trials used; a 3 mg capsule is ten times the dose that restored sleep efficiency in the 2001 MIT trial, and the timed-release capsule is 3 mg where the six-month trial used 2 mg. And matching the only modern 5-HTP trial's 100 mg says nothing about whether its finding will hold up.

About the three products. We make one side of this comparison and both forms of the other. Sleep Dots deliver 1 mg of melatonin in a dot that dissolves in the mouth, so you can stay inside the low range the trials used and adjust by the single dot.* Melatonin 3 mg Timed Release is formulated for a slower curve across the night and supports a healthy sleep-wake cycle.* Mt. Angel Vitamins 5-HTP supplies 100 mg per capsule with vitamin B6 and niacin, for people whose clinician has suggested a serotonin precursor.* All three are made in our own cGMP facility in Mt. Angel, Oregon; every batch is tested in our in-house lab for identity, potency, and purity; and the certificate of analysis is published by lot, with third-party HPLC confirmation of the 100 mg claim on the 5-HTP. Sleep Dots · Melatonin 3 mg Timed Release · Mt. Angel Vitamins 5-HTP

Next reads

• How to get the sleep your body needs: the habits every trial above assumed.
• Magnesium: forms, doses, and what the evidence supports: a bedtime staple with graded evidence and no serotonin interaction.
• How we test every lot: why lot-level identity and purity testing is the first question about any 5-HTP, ours included.