Therapeutic Use of Medical Cannabis Beyond Pain Management in Physical Medicine and Rehabilitation

Medical cannabis has emerged as a rapidly evolving therapeutic modality with expanding clinical interest beyond its traditional role in pain management. Particularly relevant to Physical Medicine and Rehabilitation (PM&R), where the focus extends beyond symptom control to functional restoration and optimal quality of life, key non-pain indications described in the literature include management of spasticity, neurologic and seizure disorders, sleep disturbances, and chemotherapy-induced nausea and vomiting (CINV). This PM&R-centered narrative review synthesizes current evidence on the efficacy, mechanisms, and clinical implications of cannabis use for non-pain conditions, with emphasis on its interaction with the endocannabinoid system, including CB1- and CB2-receptor-mediated pathways influencing neuromodulation, inflammation, and homeostasis. Across multiple conditions, cannabinoids demonstrate modest benefits in symptom reduction, including improvements in patient-reported spasticity in multiple sclerosis, significant seizure reduction in treatment-resistant pediatric epileptic syndromes, antiemetic effects in refractory CINV, and appetite stimulation in cachectic states. Additionally, subjective improvements in sleep quality have been observed, though objective changes in sleep architecture remain inconsistent. However, there remains limited evidence supporting meaningful improvements in functional outcomes and quality of life. Cannabis use may negatively impact rehabilitation through dose-dependent cognitive impairment, sedation, impaired motor learning, and increased fall risk. Significant challenges persist, including lack of standardized dosing, variability in formulations and THC:CBD ratios, inconsistent product labeling, and limited high-quality randomized controlled trials assessing long-term functional outcomes. Regulatory barriers, including discrepancies between federal and state laws, further complicate clinical implementation and research. This review highlights the gap between symptomatic relief and functional recovery, emphasizing the need for PM&R-specific research focused on rehabilitation-relevant outcomes that objectively measure functional independence and quality of life. Bridging this gap will be critical to defining a role for medical cannabis within rehabilitation medicine and optimizing patient-centered care that maximizes function.