Cannabis use among cancer survivors higher than expected

This Irish survey of 295 cancer survivors reveals that the use of biologically-based complementary and alternative medicine (BBCAM) significantly increases after a cancer diagnosis, rising from 28% pre-diagnosis to 34% post-diagnosis. Among the diverse BBCAM products used, cannabis was reported by 21% of BBCAM users, making it one of the more commonly adopted complementary approaches alongside mineral/vitamin supplements (84%), dietary supplements like turmeric and coenzyme-Q10 (78%), and herbal remedies including mistletoe, St. John's Wort, and echinacea (50%). Notably, daily BBCAM use among users dramatically increased from 38% to 72% post-diagnosis, reflecting the intensity with which cancer survivors pursue these alternatives.

Cancer survivors reported using cannabis as part of a broader strategy to manage their health after treatment, alongside special diets like ketogenic (15%), intermittent fasting (17%), and dairy-free (32%) approaches. The primary motivations for this BBCAM use centered on tangible outcomes: 63% reported improved well-being and 59% reported reduced psychological stress. However, the study highlights an important concern—many of these products, including cannabis, are unregulated and can potentially interact with conventional cancer treatments, posing health risks that survivors may not fully understand.

The findings underscore a significant gap between what conventional oncology offers and what cancer survivors feel they need to optimize their recovery and quality of life. The substantial uptake of BBCAM, particularly the use of cannabis and other botanical remedies, suggests that patients are actively seeking ways to address psychological and physical well-being beyond standard medical care. This research points to the need for greater healthcare integration around safe survivorship care, including evidence-based guidance on complementary approaches like cannabis that patients are already choosing to use.