CBN (cannabinol) is a minor cannabinoid that forms when THC oxidises as cannabis ages. It acts much more weakly than THC at the CB1 receptor, so it is far less intoxicating. Human studies on CBN and sleep are small, and their results are mixed. In the UK, cannabinol is a Class B controlled drug.
Key facts
- Chemical class
- Phytocannabinoid, formed when THC (and its acid THCA) oxidises
- Where it occurs
- Aged or stored cannabis and hemp; fresh plants contain little
- CB1 activity
- Much lower than THC in receptor studies
- Sleep research (as of October 2026)
- One 2024 trial with 293 adults, one small 2026 trial; mixed results
- UK legal status (as of October 2026)
- Class B drug under the Misuse of Drugs Act 1971 (Schedule 2, Part II)
- Formula Swiss
- We do not sell CBN oil in the UK
What is CBN and how does it form?
The plant doesn't make CBN with its own enzymes. CBN forms when THC reacts with oxygen, a process sped up by air, light and heat. That is why stored cannabis contains more CBN than fresh plant material (Fairbairn et al., 1976). A 2022 review calls CBN the "greatest" of the minor cannabinoids because of its importance in cannabis research (Maioli et al., 2022).
Because CBN comes from THC, plants bred for THC can contain more of it as they age than hemp bred for CBD. For the starting compound, see what is THC? Its varin relative, CBV (cannabivarin), forms in the same way from THCV.
How does CBN differ from THC and CBD?
| CBN | THC | CBD | |
|---|---|---|---|
| How it forms | Oxidation of THC | Made by the plant (as THCA) | Made by the plant (as CBDA) |
| CB1 receptor | Much weaker activity than THC | Partial agonist; causes the high | Low affinity; acts indirectly |
| Intoxicating | Much less than THC | Yes | No |
| UK status | Class B drug | Class B drug | Not listed as a controlled drug |
In receptor tests, CBN had much lower activity at CB1 than THC, while one of its breakdown products in the body, 11-hydroxy-CBN, was about as active as THC (Arnold et al., 2024). THC is a partial agonist at CB1 and CB2, while CBD has low affinity for both and acts in other ways (Pertwee, 2008). Our guide CBD vs CBN compares the two in more detail.
Video: what is CBN?
Is CBN legal in the UK?
No. Schedule 2, Part II of the Misuse of Drugs Act 1971 lists "Cannabinol" and "Cannabinol derivatives" as Class B drugs, alongside cannabis and cannabis resin. CBN is not listed in the UN drug conventions, and other countries treat it differently. Formula Swiss does not sell CBN oil in the UK. Our guide is CBD oil legal in the UK? explains the wider rules.
What does the research on CBN and sleep show?
CBN is often marketed for sleep, but the evidence is thin:
- Older studies: in a 1975 study of five men, CBN alone did not make them feel drowsy; combined with THC, they felt more drugged and drowsy than with THC alone (Karniol et al., 1975).
- 2021 review: the published evidence was not enough to support sleep claims (Corroon, 2021).
- 2024 trial: in 293 adults, CBN reduced night-time awakenings and overall sleep disturbance compared with placebo (Bonn-Miller et al., 2024).
- 2026 trial: in 20 adults with insomnia disorder, CBN did not change the main outcome, time awake after first falling asleep. At the higher amount, people fell asleep faster and rated their sleep better (Lavender et al., 2026).
- Animal work: CBN increased REM and non-REM sleep in rats (Arnold et al., 2024).
These are research findings about CBN taken in trials, not about any product on this store. Our guide to CBD oil and sleep covers the CBD research.
What else has CBN been studied for?
In a 2022 laboratory study, CBN protected nerve cells grown in culture from one type of oxidative cell death, acting on their mitochondria rather than on cannabinoid receptors (Liang et al., 2022). This was a cell study, and it doesn't show an effect in people.
Is CBN safe?
Safety data in people are limited to the small trials above. In lab tests, CBN inhibits the liver enzymes CYP2B6, CYP2C9 and CYP2E1, which help break down some medicines, so interactions are possible (Nasrin et al., 2021). Long-term use has not been studied. If you take medication, ask a GP or pharmacist before using any cannabinoid product. For CBD, see CBD side effects and CBD and medication interactions.
From our production
We test every batch in Switzerland, and we have never had a failed test since 2013. I sign every certificate of analysis myself. The certificate lists each cannabinoid measured in a batch, so it is the place to check what an oil contains.
— Robin Roy Krigslund-Hansen, co-founder and CEO
Our CBD oils for this store are in the CBD oil collection.
Frequently asked questions
What is CBN?
CBN, or cannabinol, is a minor cannabinoid that forms when THC oxidises as cannabis ages. Fresh plants contain little of it, and stored or aged cannabis contains more.
Is CBN legal in the UK?
No. Cannabinol and cannabinol derivatives are Class B drugs under Schedule 2, Part II of the Misuse of Drugs Act 1971. Formula Swiss does not sell CBN oil in the UK.
Is CBN psychoactive?
CBN is much less psychoactive than THC. It is much less active than THC at the CB1 receptor, and most older human studies found little cannabis-like effect from CBN alone.
How does CBN differ from CBD and THC?
THC is made by the plant and causes the high. CBN forms when THC breaks down and acts much more weakly at the same receptors. CBD is made by the plant from CBDA and is not intoxicating.
Does CBN help with sleep?
The evidence is mixed. A 2021 review found too little evidence to support sleep claims. Since then, one larger trial reported fewer night-time awakenings and a small 2026 trial found no change in its main sleep outcome.
Is CBN safe?
Safety data are limited. In lab tests CBN inhibits several liver enzymes that break down medicines, so interactions are possible. Long-term safety in people has not been studied.
This article summarises published research. It is not medical advice. Formula Swiss CBD oils are sold as cosmetics for use on the skin, and our pet oils are for external use. They are not food supplements or medicines and are not intended to diagnose, treat, cure or prevent any disease. See our full disclaimer.
Last reviewed:
Sources
- Fairbairn JW, Liebmann JA, Rowan MG. The stability of cannabis and its preparations on storage. J Pharm Pharmacol. 1976. pubmed.ncbi.nlm.nih.gov/6643/
- Maioli C, Mattoteia D, Amin HIM, et al. Cannabinol: history, syntheses, and biological profile of the greatest "minor" cannabinoid. Plants (Basel). 2022. pubmed.ncbi.nlm.nih.gov/36365350/
- Pertwee RG. The diverse CB1 and CB2 receptor pharmacology of three plant cannabinoids. Br J Pharmacol. 2008. pubmed.ncbi.nlm.nih.gov/17828291/
- Misuse of Drugs Act 1971, Schedule 2, Part II (Class B drugs). www.legislation.gov.uk/ukpga/1971/38/schedule/2
- Karniol IG, Shirakawa I, Takahashi RN, et al. Effects of delta9-tetrahydrocannabinol and cannabinol in man. Pharmacology. 1975. pubmed.ncbi.nlm.nih.gov/1221432/
- Corroon J. Cannabinol and sleep: separating fact from fiction. Cannabis Cannabinoid Res. 2021. pubmed.ncbi.nlm.nih.gov/34468204/
- 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. pubmed.ncbi.nlm.nih.gov/37796540/
- Lavender, Marshall, McCartney, et al. Cannabinol for acute treatment of insomnia disorder in a randomized placebo-controlled crossover trial. J Sleep Res. 2026. pmc.ncbi.nlm.nih.gov/articles/PMC13357646/
- Arnold, Occelli Hanbury-Brown, Anderson, et al. A sleepy cannabis constituent: cannabinol and its active metabolite influence sleep architecture in rats. Neuropsychopharmacology. 2024. pmc.ncbi.nlm.nih.gov/articles/PMC11736144/
- Liang Z, Soriano-Castell D, Kepchia D, et al. Cannabinol inhibits oxytosis/ferroptosis by directly targeting mitochondria independently of cannabinoid receptors. Free Radic Biol Med. 2022. pubmed.ncbi.nlm.nih.gov/34999187/
- Nasrin S, Watson CJW, Perez-Paramo YX, Lazarus P. Cannabinoid metabolites as inhibitors of major hepatic CYP450 enzymes, with implications for cannabis-drug interactions. Drug Metab Dispos. 2021. pubmed.ncbi.nlm.nih.gov/34493602/
