CBN vs Melatonin: What Sleep Trials and Regulators Actually Say

Melatonin is a hormone the body makes to signal night-time, and taking it mainly shifts the timing of sleep, with modest effects shown across many trials. CBN (cannabinol) is a cannabinoid that forms as THC breaks down, marketed as a sedative on the strength of a few small or industry-run studies. Melatonin has far more evidence; CBN has more marketing than data.

Their legal positions differ just as sharply. In the US, melatonin is a dietary supplement and CBN is sold as a hemp product. In the UK, melatonin is a prescription-only medicine and CBN is a controlled drug. In Canada, melatonin is a licensed natural health product sold over the counter, and CBN falls under the Cannabis Act.

This page compares how each works, what sleep trials measured, the one head-to-head study, safety, regulation in all three countries and what to check on a label. For the CBN trial data in more depth, see our report on CBN for sleep in 2026.

At a glance

Property	CBN	Melatonin
What it is	Cannabinoid formed as THC breaks down	Hormone made by the pineal gland; supplements are synthetic
Proposed sleep mechanism	Unclear; weak activity at CB1 receptors	Signals night-time to the body clock
Human sleep evidence	A few trials, mixed, several industry-run	Many trials; modest effects in meta-analysis
Average effect reported	Primary outcomes often not met	Falling asleep about 7 minutes sooner
US status	Hemp product; unclear from December 2026	Dietary supplement
UK status	Class B controlled drug	Prescription-only medicine
Canada status	Regulated under the Cannabis Act	Licensed natural health product
Workplace drug test	Can cross-react with some THC screens	Not tested for
Known label problems	CBN dose and THC content vary	US gummies measured at 74% to 347% of label
Key cautions	Sedatives, alcohol, THC content	Alcohol, sedatives, blood thinners, accidental ingestion by children

What CBN and melatonin are, and how each relates to sleep

Melatonin is made by the pineal gland as light fades, and it tells the body’s internal clock that night has arrived. Supplements and medicines use synthetic melatonin. It is better thought of as a timing signal than a sedative, which is why its best-supported uses involve shifted schedules such as jet lag.³

CBN has no such role. It is not made by the cannabis plant’s enzymes but forms as THC oxidises with age, heat and light. It has weak activity at the CB1 receptor that produces THC’s effects, and no established mechanism for promoting sleep. Sleep researchers describe it as an oxidative by-product of THC that is claimed to be a hypnotic, noting that its effects on objectively measured sleep had not been tested before their trial.⁸ Much of its reputation traces back to cannabis folklore about aged flower.

Put simply, melatonin nudges when you feel sleepy, while CBN is sold on the promise of making you sleepier. Only the first idea has a well-described biological basis.

What the sleep research shows for each

Melatonin: modest but consistent

A meta-analysis of 19 placebo-controlled trials with 1,683 participants found melatonin helped people fall asleep about 7 minutes faster and sleep about 8 minutes longer, with a small improvement in rated sleep quality.⁵ The authors described the benefit as modest, though it did not appear to fade with continued use.

Professional bodies are cautious. The American Academy of Sleep Medicine and the American College of Physicians found insufficient evidence to recommend melatonin for chronic insomnia, and cognitive behavioural therapy for insomnia is the preferred first treatment. Evidence is stronger for jet lag, where studies suggest melatonin can reduce overall symptoms and improve sleep after flights across several time zones. Evidence for shift work is weaker and of low quality.³ In Europe and the UK, a 2 mg prolonged-release tablet is licensed for short-term treatment of primary insomnia in people aged 55 and over.^1,2

CBN: a few trials, mixed results

• 20 mg nightly for a week (293 adults with poor sleep): fewer night-time awakenings and less overall disturbance, but no significant effect on the main outcome, sleep quality. The authors worked for two cannabis companies.⁹
• Single 30 or 300 mg doses in 20 adults with diagnosed insomnia, in a sleep laboratory: no change in time awake after falling asleep, the main outcome. The 300 mg dose shortened time to fall asleep and improved rated sleep quality.⁸

Our separate review of CBD for sleep covers the related cannabinoid, whose sleep evidence is similarly mixed.

The one head-to-head trial, read closely

We found only one published randomised trial that puts CBN and melatonin side by side. Around 1,000 adults took 25, 50 or 100 mg of CBN, 4 mg of melatonin or placebo. Every active group reported better sleep quality than placebo, and no CBN dose differed from melatonin.⁷

That result is often summarised as “CBN works as well as melatonin”. Three details narrow it considerably:

• Sleep was measured only by questionnaire, with no objective recording.
• The study was run by a contract research company that employed the authors, and it tested one maker’s proprietary CBN product.
• It has not been independently repeated, and the one independent sleep-laboratory trial of CBN missed its main outcome.⁸

A fair reading is that both beat placebo on self-report in one industry study. It does not show that CBN matches melatonin’s broader evidence base, and it says nothing about long-term use of either.

Safety, side effects, interactions and drug testing

Melatonin

Short-term side effects are usually mild: headache, dizziness, nausea and drowsiness. Long-term effects are unclear.³ The NHS warns against combining melatonin with alcohol and lists interactions with medicines including fluvoxamine, warfarin, benzodiazepines, opioids and some antibiotics. It also notes that using cannabis alongside melatonin increases its sleep-inducing effects.¹ Health Canada’s labelling standard tells users to avoid driving for 5 hours after a dose and not to use it in pregnancy or while breastfeeding.⁴

Children are the clearest concern in the US. Calls to US poison centres about melatonin in children and teenagers rose from 8,337 in 2012 to 52,563 in 2021, mostly accidental ingestion by young children.³ Gummies that look like sweets are a large part of that picture.

CBN

Short trials report mostly mild adverse events, and the sleep-laboratory study logged 247 mild-to-moderate events across its three arms, including placebo.⁸ There are no long-term safety data and little interaction research. Combining CBN with alcohol, sleeping tablets or other sedatives, or with melatonin, has not been studied.

CBN also carries a drug-testing issue melatonin does not. Two commercial urine immunoassays for THC metabolite cross-reacted with CBN in laboratory testing, and many CBN products also contain THC.¹⁰

Why melatonin is a medicine in one country and a supplement in another

United States. Melatonin is regulated as a dietary supplement, so it is not approved for any condition and products do not go through FDA review before sale.³ CBN is sold as a hemp-derived cannabinoid. A federal law passed in November 2025 caps finished hemp products at 0.4 mg of total THC per container and excludes cannabinoids synthesised or manufactured outside the plant. Most provisions start on 11 December 2026, while those on cannabinoids not naturally occurring in the plant keep a 12 November date.¹² Because commercial CBN is often made by converting other cannabinoids, its status is unclear until the FDA publishes its cannabinoid lists. State rules also vary.

United Kingdom. Melatonin is a prescription-only medicine. The NHS says melatonin supplements are not authorised for sale in the UK and advises against ordering it online.¹ Licensed products are prescribed mainly for short-term sleep problems in people aged 55 and over, and by specialists for some children and adults.^1,2 Cannabinol is a Class B controlled drug under the Misuse of Drugs Act 1971.¹¹ Neither is a lawful over-the-counter purchase in the UK.

Canada. Melatonin is licensed as a natural health product under a Health Canada monograph for adults, with set label warnings.⁴ CBN, like other phytocannabinoids, is regulated under the Cannabis Act and sold only through authorised cannabis retailers.

Labels, dose accuracy and combination products

Supplement status has not meant accurate labels. When researchers tested 25 US melatonin gummy products, 22 did not contain an amount within 10% of the label, with melatonin ranging from 74% to 347% of the stated dose. Some products labelled as containing CBD held 104% to 118% of the stated CBD.⁶

CBN products have their own problems: marketed doses are often far below the 20 to 300 mg used in trials, and THC content varies with the extract and conversion method. Many “sleep” gummies also combine CBN with melatonin, which makes it impossible to know which ingredient is doing what.

• For melatonin in the US: look for third-party verification of content, and store gummies out of reach of children.
• For CBN: ask for a batch-matched certificate of analysis from an ISO/IEC 17025 accredited laboratory showing CBN, delta-9 THC, delta-8 THC and residual solvents.
• For blends: check the milligrams of each active ingredient per serving, not just the total.

UK readers should note that the kinds of US gummies tested in these studies are not authorised for sale in the UK, and the NHS advises against ordering melatonin online.¹ Our guide to the signs a brand is genuinely third-party tested explains what a credible lab report looks like.

Frequently asked questions

Is CBN better than melatonin for sleep?

The evidence does not show that. The only head-to-head trial found CBN and 4 mg of melatonin both beat placebo on a questionnaire, with no difference between them, in a study run by an industry contractor.⁷ Melatonin has many more trials behind it, though its average benefit is modest.⁵ Ongoing insomnia is worth raising with a clinician.

Can you take CBN and melatonin together?

Many sleep gummies combine them, but no trial has tested the combination for safety or benefit. The NHS notes that cannabis can increase melatonin’s sleep-inducing effects, so additive drowsiness is plausible.¹ Avoid combining either with alcohol or sleeping tablets, and speak to a pharmacist if you take other medicines. In the UK, neither is available over the counter.

Can you buy melatonin over the counter in the UK?

No. Melatonin is a prescription-only medicine in the UK, and the NHS states that melatonin supplements are not authorised for sale there. It advises against ordering melatonin online.¹ Licensed melatonin is prescribed mainly for short-term sleep problems in people aged 55 and over, and by specialists for some other patients.

Does CBN make you groggy the next day?

Limited data suggest not at the doses tested. In a week-long trial, 20 mg of CBN a night did not change daytime fatigue compared with placebo.⁹ Higher doses, products containing THC, and combinations with other sedatives have not been well studied for next-day effects, so avoid driving until you know how a product affects you.

Is it safe to take melatonin every night?

Short-term use is generally associated with mild side effects such as headache, dizziness, nausea and drowsiness, but the long-term effects of regular use are unclear.³ Health Canada’s labelling standard advises seeing a practitioner if sleeplessness lasts more than four weeks.⁴ In the UK, nightly use would be under a prescriber’s supervision.

Sources

1. NHS. Melatonin: about melatonin; common questions about melatonin; taking melatonin with other medicines and herbal supplements. nhs.uk
2. European Medicines Agency. Circadin (melatonin) 2 mg prolonged-release tablets: EPAR summary. Marketing authorisation 29 June 2007. ema.europa.eu
3. National Center for Complementary and Integrative Health. Melatonin: What You Need To Know. Updated May 2024. nccih.nih.gov
4. Health Canada. Natural Health Product Monograph: Melatonin, Oral. 19 December 2025. hc-sc.gc.ca
5. Ferracioli-Oda E, Qawasmi A, Bloch MH. Meta-analysis: melatonin for the treatment of primary sleep disorders. PLoS One. 2013;8(5):e63773. DOI: 10.1371/journal.pone.0063773. PMID: 23691095. pubmed.ncbi.nlm.nih.gov
6. Cohen PA, Avula B, Wang YH, Katragunta K, Khan I. Quantity of Melatonin and CBD in Melatonin Gummies Sold in the US. JAMA. 2023;329(16):1401-1402. DOI: 10.1001/jama.2023.2296. PMID: 37097362. pubmed.ncbi.nlm.nih.gov
7. Kolobaric A, Saleska J, Hewlings SJ, et al. A Randomized, Double-Blind, Placebo-Controlled Trial to Assess the Effectiveness and Safety of Melatonin and Three Formulations of Floraworks Proprietary TruCBN for Improving Sleep. Pharmaceuticals (Basel). 2024;17(8):977. DOI: 10.3390/ph17080977. PMID: 39204082. pubmed.ncbi.nlm.nih.gov
8. Lavender IG, Marshall NS, McCartney D, et al. Cannabinol for Acute Treatment of Insomnia Disorder in a Randomized Placebo-Controlled Crossover Trial. J Sleep Res. 2026;35(4):e70284. DOI: 10.1111/jsr.70284. PMID: 41698831. pubmed.ncbi.nlm.nih.gov
9. Bonn-Miller MO, Feldner MT, Bynion TM, et al. A double-blind, randomized, placebo-controlled study of the safety and effects of CBN with and without CBD on sleep quality. Exp Clin Psychopharmacol. 2024;32(3):277-284. DOI: 10.1037/pha0000682. PMID: 37796540. pubmed.ncbi.nlm.nih.gov
10. Kroner GM, Johnson-Davis KL, Doyle K, McMillin GA. Cannabinol (CBN) Cross-Reacts with Two Urine Immunoassays Designed to Detect Tetrahydrocannabinol (THC) Metabolite. J Appl Lab Med. 2020;5(3):569-574. DOI: 10.1093/jalm/jfaa020. PMID: 32445358. pubmed.ncbi.nlm.nih.gov
11. UK Home Office. Drug Licensing Factsheet: Cannabis, CBD and other cannabinoids. Revised September 2024. gov.uk
12. Hemp Law Group. Federal Hemp Law in 2026: The Ban, the Deadline, and Every Bill Trying to Change It. Updated September 2026. hemplawgroup.com

Editorial note: This article is for general information only and is not medical or legal advice. CBN products have not been evaluated by the FDA to diagnose, treat, cure or prevent any disease. Melatonin is sold as a dietary supplement in the US but is a prescription-only medicine in the UK, where it should be used only as prescribed. Laws vary by location and change often, so verify the rules that apply where you are. Always talk to a licensed healthcare provider before use, especially if you are under 21, pregnant or nursing, taking medication, or managing a health condition.