Chronic Δ9-tetrahydrocannabinol exposure during adolescence is associated with persistent behavioural tolerance in adult nonhuman primates.
British journal of pharmacology November 1, 2025 Yasaman Razavi, Stephen J Kohut, Jack Bergman et al. 1 citation
Adolescent monkeys exposed daily to the cannabis compound Δ9-THC for six months, then tested about a year later as adults on a touchscreen attention task, required higher acute doses of Δ9-THC to impair their performance compared with animals that had not been exposed during adolescence. The impairment itself was dose-related and occurred whether the drug was given by injection or orally, though potency and timing differed. These results suggest that heavy cannabis use during adolescence can produce a lasting tolerance that persists into adulthood, even after a long period of abstinence.