Cannabis-Based Medicines for Nociplastic Pain: A Scoping Review of Efficacy, Safety, and Patient Outcomes.

Abstract

Cannabis-based medicines (CBM) are increasingly considered for nociplastic pain (NOCP) despite limited evidence. This scoping review mapped evidence on efficacy, safety, patient-reported outcomes, and pharmacokinetic/pharmacodynamic (PK/PD) considerations for CBM in NOCP. MEDLINE, Cochrane Library, Web of Science, and Scopus were searched through 2024. Eligibility included patients with NOCP or a nociplastic phenotype, any setting, any study design, and English language. Data were charted inductively, synthesized narratively, and risk of bias was assessed. Ten studies were included, predominantly secondary (reviews/opinions, consensus), with very limited primary data linking CBM to nociplastic mechanisms. Signals suggest modest benefits in fibromyalgia and chronic musculoskeletal pain, with improvements more evident for sleep, affective domains, and quality-of-life than for direct analgesia. Adverse effects were common (e.g., sedation, dizziness, psychiatric symptoms), particularly with tetrahydrocannabinol-dominant products. PK findings included low/variable oral bioavailability (∼6%), food and hepatic effects (notably for cannabidiol), and prolonged terminal half-life; PD effects included psychomotor and cognitive impairment. No study applied standardized nociplastic instruments. Co-administration cautions with opioids were noted, but no phenotype-specific opioid-sparing evidence was identified. Overall, evidence remains low-certainty and indirect, supporting adequately powered, longer-term trials with explicit NOCP phenotyping and standardized formulations. CBM show outcome-specific benefits balanced against dose- and formulation-dependent harms.