Medical Cannabis for Multiple Sclerosis Spasticity: A Cochrane Review
Abstract
Moderate-quality evidence supports nabiximols (Sativex) for MS spasticity. Patient-reported spasticity improved significantly vs. placebo in 6 of 7 included RCTs. Adverse effects were common but generally mild and transient.
Study Summary
This Cochrane systematic review and meta-analysis included 7 RCTs (n=1,534) examining nabiximols (Sativex, 1:1 THC:CBD oromucosal spray) for multiple sclerosis-related spasticity. Studies were identified through the Cochrane MS and Rare Diseases Group Specialised Register. The primary outcome was patient-reported spasticity on a 0–10 NRS. Nabiximols significantly reduced spasticity NRS scores vs. placebo (MD −1.41, 95% CI −1.86 to −0.96) — a clinically meaningful reduction. 6 of 7 RCTs showed significant benefit. Secondary outcomes including sleep disturbance, pain, and bladder dysfunction also improved. Adverse effects were common (dizziness 32%, fatigue 24%, nausea 18%) but generally mild and transient. Serious adverse events were not significantly different from placebo. The authors rated evidence quality as moderate (GRADE), limited by risk of unblinding due to psychoactive effects.
Key Findings
- 1Nabiximols reduced MS spasticity NRS by −1.41 points vs. placebo (clinically meaningful)
- 26 of 7 RCTs showed significant spasticity benefit — consistent evidence base
- 3Sleep, pain, and bladder dysfunction also significantly improved
- 4Adverse effects common (dizziness 32%, fatigue 24%) but mild and transient
- 5GRADE evidence quality: moderate — limited by unblinding risk
Clinical Implications
- Nabiximols is an evidence-based option for MS spasticity refractory to first-line treatments
- A 4-week trial period is recommended to identify responders (≥20% NRS improvement)
- Dizziness and fatigue are expected early adverse effects that typically resolve
- Nabiximols is approved in 30+ countries for MS spasticity but not yet in the US
Study Limitations
- All studies used nabiximols — evidence may not generalize to other cannabinoid formulations
- Blinding integrity compromised by psychoactive effects in some participants
- Long-term efficacy and safety data (>12 months) limited
- Objective spasticity measures (Ashworth scale) less consistently improved than patient-reported