Half of Danish MS patients have used cannabis, mostly illegally, reporting high efficacy for pain and spasticity | Research

The takeaway

In the largest MS cannabis survey to date, 49% of 2,009 Danish patients had used cannabis, with 21% using currently. Only 21% of current users had prescriptions, yet patients reported high efficacy for pain (61%), spasticity (52%), and sleep (46%) with mild adverse effects.

People with MS considering cannabis, healthcare providers treating MS, and policymakers in countries with restrictive cannabis access.

49% of MS patients used cannabis; only 21% of users had prescriptions

What the researchers found

49% had tried cannabis, 21% were current users, and only 21% of current users had prescribed cannabis. Recreational/illegal use was reported by 17%. Primary use reasons: pain relief (61%), spasticity (52%), sleep disturbances (46%). Most common adverse effects: drowsiness (30%), feeling subdued (23%), dizziness (13%). 44% of non-users would consider cannabis if legalized.

Why it matters

This is the most comprehensive MS cannabis use survey published. The gap between patient demand (49% have tried, 44% of non-users would consider) and prescription access (only 21% of users have prescriptions) reveals a massive unmet need being filled by illegal channels.

The numbers in context

3,606 surveyed, 2,009 valid responses (62% response). 49% ever used cannabis. 21% current users. Only 21% of current users had prescriptions. Pain: 61%. Spasticity: 52%. Sleep: 46%. Adverse effects mild: drowsiness 30%, subdued feeling 23%, dizziness 13%.

How the study worked

Anonymous questionnaire sent to all 3,606 patients at the Danish Multiple Sclerosis Center (62% response rate, 2,009 valid responses), covering sociodemographic factors, clinical characteristics, and cannabis use patterns.

What this study cannot tell us

Self-reported efficacy without objective measures or placebo comparison. 38% non-response rate may introduce bias. Danish regulatory environment specific. Survey cannot establish whether cannabis is genuinely effective or reflects placebo/expectancy effects.

How to read the evidence

Moderate: comprehensive survey of an entire MS center population with good response rate, but self-reported outcomes without controls.

When this study was published

Published in 2019.

The bigger picture

When patients report high efficacy and mild side effects but mostly use illegally, the regulatory system is failing them. This pattern is likely replicated across many countries where medical cannabis access is restricted while patient need is high.

Questions still open

Would controlled trials confirm the high patient-reported efficacy? What prevents Danish prescribers from recommending cannabis more frequently? Would legalization lead to more or fewer MS patients using cannabis?

Common questions

Do MS patients find cannabis helpful?

In this survey of 2,009 Danish MS patients, current cannabis users reported high efficacy for pain (61%), spasticity (52%), and sleep (46%). Adverse effects were predominantly mild. However, this is patient self-report without placebo controls.

Why are most MS patients using cannabis illegally?

Only 21% of current cannabis users in this study had prescriptions, likely reflecting strict Danish regulations. The gap between patient demand and prescription access means most patients obtain cannabis through illegal channels.

Read the original research

Illegal cannabis use is common among Danes with multiple sclerosis.

Multiple sclerosis and related disorders, 33, 5-12

View on PubMed ↗Publisher’s paper ↗

Citation

Gustavsen, S; Søndergaard, H B; Andresen, S R; Magyari, M; Sørensen, P S; Sellebjerg, F; Oturai, A B. (2019). Illegal cannabis use is common among Danes with multiple sclerosis.. Multiple sclerosis and related disorders, 33, 5-12. https://doi.org/10.1016/j.msard.2019.05.008