Peptides for sleep: what the human studies show, peptide by peptide

Searches for "peptides for sleep" more than doubled in a year, from about 2,900 a month in September 2025 to 6,600 in August 2026 (Google Ads data). The pages that rank mostly sell peptides or prescribe them. We went back to the human studies themselves.

Which peptides for sleep have been tested in humans?

Very few, and only in small groups. Here is every peptide commonly sold for sleep, with the best human study we could find and what it showed.

Two patterns stand out. The positive studies all gave the peptide by vein or nasal spray in a sleep lab, often for one night. And no study tested the injected research vials that sleep-peptide guides recommend.

Does DSIP work for sleep?

Probably not. DSIP got its name in 1977, when Swiss researchers found that it increased deep-sleep EEG activity in rabbits. Human studies followed between 1981 and 1998. All were small, all were intravenous, and the best-controlled one was negative. In that trial, 16 people with chronic insomnia received DSIP or placebo for three nights. Their subjective sleep did not improve, and the authors concluded DSIP "is not likely to be of major therapeutic benefit" (Bes 1992).

FDA reviewed all of it in July 2026 and called the insomnia data "inconclusive and at best preliminary". Its Pharmacy Compounding Advisory Committee then voted 7-6 against letting pharmacies compound it. No study has ever tested DSIP injected under the skin, the way research vials are used. Every study, the FDA review and the vote are laid out on our DSIP page.

Do growth-hormone peptides improve deep sleep?

This is where the real human data are, and they belong to GHRH, the body's own growth hormone-releasing hormone. Sermorelin is its first 29 amino acids. Tesamorelin and CJC-1295 are modified versions built to last longer.

What the sleep-lab studies found:

• Steiger 1992. Seven healthy men got four IV doses of GHRH through the night. Time in slow-wave sleep rose from 14.0% on placebo to 20.2%, and night-time cortisol fell (Neuroendocrinology).
• Kerkhofs 1993. In young men, GHRH given late in the night cut time awake and raised slow-wave sleep almost tenfold for that period. Given early in the night, it raised REM sleep but did not change deep sleep (Am J Physiol).
• Perras 1999. GHRH as a nasal spray at bedtime, tested in 12 young and 11 older men, increased both REM and slow-wave sleep, mainly in the second half of the night. The effect did not depend on age (Psychoneuroendocrinology).
• Murck 1997. In older people, GHRH had "only weak effects" on sleep, and 12 days of pre-treatment did not restore them. That was a pilot study in two people (Pharmacopsychiatry).

The longer test never reported. A University of Washington trial of GHRH for age-related sleep problems (NCT00000380) is listed as completed, with no results posted. Two later sleep trials of GHRH and of tesamorelin (Egrifta) were withdrawn before enrolling anyone.

Read together, the studies show that GHRH can deepen sleep for a night in healthy young men in a lab. Nobody has shown that sermorelin, CJC-1295 or tesamorelin improves sleep in people who sleep badly, which is what the clinics selling them for sleep imply. Our tesamorelin vs sermorelin comparison covers how the molecules differ.

Do ipamorelin or MK-677 help sleep?

Ipamorelin has no sleep study. The case for it borrows from two relatives that act on the same ghrelin receptor:

• Ghrelin itself. Four IV doses through the night increased slow-wave sleep across the night in 7 people (Weikel 2003).
• MK-677 (ibutamoren). In 8 young adults, a week of the high dose at bedtime raised stage-4 deep sleep by about 50% and REM sleep by more than 20% against placebo. In 6 adults aged 65 to 71, REM rose by nearly 50% (Copinschi 1997). MK-677 is a pill, and it is not a peptide.

That is 21 people across two studies, for one to two weeks. It suggests the ghrelin receptor matters for sleep. It does not tell you what an ipamorelin injection does. The two growth-hormone routes are compared in CJC-1295 vs ipamorelin.

Is epitalon a sleep peptide?

Only indirectly. Epitalon is a four-amino-acid peptide from the St. Petersburg group led by Vladimir Khavinson. That group reported that epitalon and the pineal extract epithalamin restored night-time melatonin release in older monkeys and older people (Korkushko 2007). A 79-patient study by the same group, using the pineal extract, also reported a normalised melatonin rhythm (2011).

None of those studies measured sleep as its main outcome. None was replicated by an independent group. Even so, epitalon was nominated to FDA for insomnia, and in July 2026 the compounding advisers voted to recommend it, over the objection of FDA's own reviewers. A recommendation is not a legal pathway yet. The vote is covered on our epitalon page and in the July vote explainer.

Do Selank or collagen peptides help sleep?

Selank was developed in Russia as an anti-anxiety peptide. Calmer people may fall asleep more easily, but we found no human study that measured sleep, and ClinicalTrials.gov lists none.

Collagen peptides are the one oral option with a controlled sleep study. In a crossover trial, 13 athletic men with sleep complaints took 15 g a night for a week. Polysomnography showed fewer awakenings (21 against 29), but total sleep, time to fall asleep and sleep efficiency did not change. The collagen manufacturer supplied the product, and two authors were its employees (Thomas 2024).

What actually treats insomnia?

The treatments with strong evidence are not research peptides.

• CBT-I. Cognitive behavioural therapy for insomnia is the recommended first treatment for chronic insomnia in adults, in guidance from the American College of Physicians (2016) and the American Academy of Sleep Medicine (2021).
• Orexin receptor antagonists. Orexin is a neuropeptide that keeps the brain awake. Suvorexant (approved 2014), lemborexant (2019) and daridorexant (2022) block its receptors. They are the approved drugs that work through a peptide system, but they are small-molecule pills, not peptides.
• Other prescription sleep drugs and melatonin have trial records far larger than any study above.

If a clinic or a seller offers a peptide for sleep, it is asking you to swap these for compounds tested in a few dozen healthy men, mostly in the 1990s.

What should you check before trusting a "sleep peptide" listing?

If you are reading vendor pages anyway, three checks separate a defensible listing from marketing:

1. Does the claim match a study? "Promotes deep sleep" on a CJC-1295 or ipamorelin page borrows from GHRH or MK-677 research, not from the product.
2. Is the vial what it says? In our lab corpus, one of 24 DSIP analyses found an empty vial. A certificate covers only the batch the lab tested. Check it against the issuing lab with our COA verifier.
3. Is the seller giving dosing directions? FDA treats dosing instructions on a "research use only" site as evidence that the product is meant for people. Our enforcement timeline explains why that matters.

Vendor-level audits are on our vendor pages.

Sources

• Bes et al. 1992, DSIP in chronic insomnia, double-blind (Neuropsychobiology) - 16 patients, negative on subjective sleep
• FDA briefing document, emideltide (DSIP), Pharmacy Compounding Advisory Committee, July 2026 - "inconclusive and at best preliminary"
• Steiger et al. 1992, GHRH and somatostatin on sleep EEG (Neuroendocrinology) - slow-wave sleep 14.0% vs 20.2%
• Kerkhofs et al. 1993, sleep-promoting effects of GHRH in normal men (Am J Physiol)
• Perras et al. 1999, intranasal GHRH in young and aged men (Psychoneuroendocrinology)
• Murck et al. 1997, GHRH in old-aged subjects (Pharmacopsychiatry)
• Weikel et al. 2003, ghrelin promotes slow-wave sleep in humans (Am J Physiol Endocrinol Metab)
• Copinschi et al. 1997, MK-677 improves sleep quality (Neuroendocrinology)
• Korkushko et al. 2007, pineal peptides and melatonin rhythm (Adv Gerontol) and Korkushko et al. 2011 (Bull Exp Biol Med)
• Thomas et al. 2024, collagen peptides and sleep fragmentation (Eur J Nutr)
• ClinicalTrials.gov, NCT00000380, GHRH for age-related sleep disturbances and registry search for each peptide with sleep or insomnia, 13 October 2026
• American College of Physicians 2016 guideline and American Academy of Sleep Medicine 2021 guideline on CBT-I as first-line treatment
• Search volume: Google Ads keyword data for "peptides for sleep", United States, September 2025 to August 2026