Age-Related Effects of Cannabis and Cannabinoids on Brain and Behavior.

Introduction: The effect of cannabis use on health is likely to depend on individual differences. In particular, there is a growing need to understand the impact of cannabis and delta-9-tetrahydrocannabinol (THC) on brain and behavioral health across the lifespan. Materials and Methods: We conducted a narrative review summarizing the effects of cannabis and THC across three stages of life: in utero, adolescence, and late adulthood. We also provide an up-to-date report on past 30-day cannabis use and risk perceptions from the National Survey on Drug Use and Health (NSDUH; 2002-2023) during pregnancy, adolescence, and late adulthood. We note that NSDUH data collected during 2020 and since 2021 are not directly comparable to earlier years due to shifts in data collection methods. Results: Recent epidemiological data indicate a potential reversal of both the escalating rates of cannabis use and low perceptions of risk among pregnant women and adolescents. Findings across preclinical and clinical studies support high perceptions of risk for individuals in utero and adolescence, when alterations in brain development indicate potential for susceptibility to neuropsychiatric disorders. The escalating rates of cannabis use and associated low perceptions of risk have shifted to the late adulthood population, which may face unique health risks associated with cannabis use. Conclusions: Our findings emphasize the necessity for clinical and policy recommendations to mitigate the risks associated with cannabis use and to enhance public understanding of its implications on neurodevelopmental and psychiatric disorders. Continued research and educational strategies are essential to address these evolving trends and reduce harm.