Multiple Sclerosis Spasticity
Nabiximols (Sativex) approved in 30+ countries for MS-related spasticity
MS-related spasticity has one of the strongest evidence bases for cannabinoid therapy outside of epilepsy. Nabiximols (Sativex — a 1:1 THC:CBD oromucosal spray) is approved in over 30 countries, though not yet in the U.S.
At a Glance
Overview
Multiple sclerosis affects approximately 1 million Americans. Spasticity — involuntary muscle stiffness and spasms — affects 60–80% of MS patients and is a major source of disability, pain, and reduced quality of life. Conventional treatments (baclofen, tizanidine, diazepam) are often inadequate or poorly tolerated.
Nabiximols (Sativex) is a standardized cannabis extract containing THC and CBD in a 1:1 ratio, delivered as an oromucosal spray. It has been approved in over 30 countries (including Canada, UK, Germany, and most of Europe) for MS-related spasticity, though it has not received FDA approval in the U.S. (where it remains in Phase III trials).
The pivotal evidence comes from the MUSEC trial (n=279), published in the Journal of Neurology Neurosurgery and Psychiatry in 2012, which found nabiximols produced a significant reduction in patient-reported spasticity scores versus placebo. A 2010 European Journal of Neurology RCT (n=189) found 74.6% of nabiximols-treated patients reported improvement in spasticity versus 51.0% for placebo.
A 2014 Cochrane review of 12 RCTs found cannabis-based medicines significantly reduced patient-reported spasticity (SMD −0.36) and spasm frequency. Objective measures (Ashworth scale) showed smaller effects, suggesting patient-reported outcomes capture benefits that clinician-rated scales miss.
The mechanism involves CB1 receptor-mediated reduction of glutamate release in spinal interneurons, reducing the hyperexcitability that underlies spasticity. CBD's contribution may include anti-inflammatory effects on the demyelinating process.
Symptoms
- Muscle stiffness and rigidity
- Involuntary muscle spasms
- Pain associated with spasms
- Reduced range of motion
- Clonus (rhythmic muscle contractions)
- Bladder dysfunction
- Sleep disruption from spasms
How Cannabis Helps
CB1 receptor activation in spinal interneurons reduces glutamate release, decreasing the hyperexcitability underlying spasticity. THC and CBD together (as in nabiximols) produce greater spasticity reduction than either alone, suggesting synergistic mechanisms.
Treatment Options
Graded by quality of evidence. Grade A = strong (RCTs/FDA approval); B = moderate; C = preliminary.
Nabiximols (THC:CBD 1:1)
Oromucosal spray (Sativex)
Approved in 30+ countries. Multiple RCTs show significant patient-reported spasticity reduction.
Not FDA-approved in U.S. Available in Canada, UK, EU. 2.7 mg THC + 2.5 mg CBD per spray.
Oral cannabis extract (THC:CBD)
Oral capsule
Cochrane review supports efficacy. Slower onset than oromucosal spray.
Inhaled cannabis
Vaporized
Rapid onset. Small RCTs show spasticity reduction. Dose control more challenging.
Key Studies
Primary literature supporting the evidence grade for this indication.
MUSEC trial: nabiximols for MS spasticity
Grade AJournal of Neurology Neurosurgery and Psychiatry, 2012
n=279. Nabiximols significantly reduced patient-reported spasticity vs. placebo (p=0.0002).
Randomized controlled trial of nabiximols for MS spasticity
Grade AEuropean Journal of Neurology, 2010
n=189. 74.6% nabiximols vs. 51.0% placebo reported spasticity improvement.
Cannabis-based medicines for multiple sclerosis
Grade ACochrane Database, 2014
12 RCTs. Significant reduction in patient-reported spasticity (SMD −0.36).
Side Effects to Watch
- Dizziness and balance impairment (relevant in MS patients with existing balance issues)
- Cognitive effects with high-dose THC
- Oral mucosal irritation (oromucosal spray)
- Sedation
- Falls risk
Who Should Avoid
- Severe psychiatric comorbidity
- History of psychosis
- Pregnancy
- Severe hepatic impairment
Dosing Guidance
Nabiximols: start with 1 spray at bedtime, titrate by 1 spray every 3 days to effect (typical maintenance: 4–8 sprays/day, max 12/day). Administer to oral mucosa, rotating sites. Allow 15 minutes between sprays during titration.
Dosing information is for educational purposes only. Consult a licensed healthcare provider for personalized guidance.
Clinician Note
Nabiximols is the most evidence-supported cannabinoid formulation for MS spasticity and should be the preferred option where available. In the U.S., patients may access cannabis through state medical programs. Patient-reported outcomes are more sensitive than Ashworth scale for detecting treatment response.
Related Conditions
Medical Disclaimer: This content is for educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Cannabis remains a Schedule I controlled substance federally in the U.S. Always consult a qualified healthcare provider before making any medical decisions. Individual responses to cannabinoids vary significantly.