Beyond opioids: cannabis and the changing landscape of cancer pain

Background: Opioids are the primary therapy for cancer-related pain; however, their adverse effects and risk of dependence highlight the need for alternatives. Cannabinoids, including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), have emerged as potential adjuncts and substitutes. Methods: We conducted targeted searches of PubMed, Embase, and the Cochrane Library (2015–2025) for randomized controlled trials, systematic reviews, and observational studies on the use of cannabis for cancer pain. The evidence was stratified according to methodological rigor, with randomized and systematic data forming the evidentiary core. Results: Early trials suggested that THC- and CBD-containing products provide analgesia in opioid-refractory cancer pain, but more recent meta-analyses reported only modest benefits compared with placebo or standard therapy. Patient-specific factors, such as age, sex, comorbidities, and concomitant medications, influence the outcomes. Routes and dosing strategies affect efficacy, with oral and oromucosal formulations showing delayed onset and inhaled forms producing faster but shorter analgesia. Real-world surveys report favorable patient perceptions, although misconceptions, such as cannabis as a “cure” remain common. Safety data indicate mostly mild, dose-dependent adverse events; however, long-term risks include hyperemesis and possible carcinogenic associations. Conclusions: Current evidence does not support cannabis as a stand-alone analgesic; however, it may contribute to individualized, multimodal cancer pain management. Future research should standardize dosing, compare delivery methods, and evaluate cannabis in combination with established pharmacological and non-pharmacological modalities.