From ancient remedy to modern use: cannabis and cannabinoids in cancer care in the United States

Cannabis, an ancient plant that has been used for millennia, is increasingly utilized by patients with cancer to alleviate symptoms related to both the disease and its treatment. This complex botanical contains multiple bioactive compounds, most notably delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), which interact with the endogenous endocannabinoid system. THC has been studied the most, and synthetic cannabinoids are approved for the management of chemotherapy-induced nausea and vomiting. However, evidence supporting cannabis for other cancer-related symptoms—including chemotherapy-induced peripheral neuropathy, insomnia, appetite stimulation, and non-neuropathic pain—remains limited. CBD alone has not demonstrated consistent or meaningful clinical benefit. Although preclinical data exist, there is no clinical evidence supporting cannabis as a cancer treatment. Cannabis may interact with prescribed medications, particularly with high-dose oral formulations, and its effects on immunotherapy are under investigation. Overall, cannabis is generally well tolerated, though adverse effects can be significant. Use is discouraged in individuals under 25 years of age due to ongoing neurodevelopment, and patients with active psychiatric or cardiovascular conditions should use cannabis only under close clinical supervision.