Supplement analysis backed by scientific evidence · PT

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CBN (Cannabinol)

CBN's reputation as 'the sleepy cannabinoid' came from 1970s pharmacology that never actually showed it was sedating on its own. Two modern RCTs now exist: one found modest reductions in night-time awakenings at 20 mg, the other found CBN added nothing to CBD or melatonin.

What the science says

  • CBN is inherently sedating Limited evidence

    The origin story is a 1975 human study showing cannabinol had little effect alone but potentiated THC's effects — the opposite of proof that CBN is a sedative. The 'aged cannabis becomes sedating because THC degrades to CBN' explanation has never been demonstrated experimentally; degraded cannabis also loses terpenes and potency.

  • 20 mg CBN nightly improves sleep Limited evidence

    In a double-blind placebo-controlled trial (n=293 self-rated poor sleepers, 7 nights), 20 mg CBN produced a non-significant effect on the primary endpoint of sleep quality (OR 2.26, 95% CI 0.93-5.52, p=0.082) but significantly reduced number of awakenings and overall sleep disturbance (both p≈0.02), with no effect on sleep onset latency, wake after sleep onset, or daytime fatigue. Positive on secondary endpoints only, over a single week, in an industry-run trial.

  • Adding CBN to CBD or melatonin makes the product work better Limited evidence

    A 1,793-participant, 4-week randomised trial compared six capsule formulations and found no significant difference between 15 mg CBD isolate and formulations adding 15 mg CBN (with or without CBC), and no advantage over 5 mg melatonin alone. The authors concluded that low doses of CBN and CBC may not improve formulations containing CBD or melatonin isolate — which is precisely what most 'CBN for sleep' gummies are selling.

  • CBN is non-psychoactive Moderate evidence

    CBN is a weak partial agonist at CB1 receptors — far weaker than THC but not inert — and hemp-derived CBN products routinely contain trace THC. That is enough to matter for drug testing: CBN products have been associated with positive urine cannabinoid screens, and no CBN product should be assumed THC-free.

Dosage & safety

Studied doseTrial doses are 20 mg nightly (Bonn-Miller, 7 nights) and 15 mg nightly as part of a blend (Saleska, 4 weeks); a proof-of-concept insomnia trial has tested 30 mg and 300 mg. Commercial gummies typically supply 3-10 mg of CBN, below anything tested. There is no established effective dose, and dose-response has not been mapped.
SafetyShort-term trials report mild adverse events — drowsiness, dry mouth, GI upset — with no serious events, but there are no safety data beyond a few weeks. Like other cannabinoids, CBN is metabolised by CYP enzymes and may interact with sedatives, anticoagulants and antiepileptics; CBD-containing co-formulations have well-documented interactions. Legal status is unsettled: CBN is not explicitly scheduled in the US but hemp-derived cannabinoid products fall in a regulatory grey zone, FDA has stated cannabinoids are not lawful dietary ingredients, and rules vary by state and country. Products can contain THC above hemp thresholds and can cause a failed workplace or sport drug test. Not for use in pregnancy, breastfeeding, or by anyone under 18.

Scientific references

Where to buy

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