Cannabinol (CBN; 30 and 300 mg) effects on sleep and next-day function in insomnia disorder (‘CUPID’ study): protocol for a randomised, double-blind, placebo-controlled, cross-over, three-arm, proof-of-concept trial

Abstract Objective: Insomnia is the most prevalent sleep disorder, with few effective pharmacotherapies. Anecdotal reports and recent preclinical research suggest that cannabinol (CBN), a constituent of Cannabis sativa derived from delta-9-tetrahydrocannabinol, could be an effective treatment. Despite this, the isolated effects of CBN on sleep have yet to be systematically studied in humans. Methods: The present protocol paper describes a randomised, double-blind, placebo-controlled, single-dose, three-arm, cross-over, proof-of-concept study which investigates the effects of CBN on sleep and next-day function in