Medical cannabis improved sleep, fatigue, and pain for patients with muscle spasticity or spasms, but not physical functioning

In 150 patients, medical cannabis did not improve physical functioning, but CBD-only products helped spasticity patients with sleep, fatigue, and pain, while THC-containing products helped spasm patients similarly.

Nastatos, Xenia L et al.·The Journal of pharmacology and experimental therapeutics·2026·Moderate EvidenceLongitudinal Cohort
RTHC-08516Longitudinal CohortModerate Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Longitudinal Cohort
Evidence
Moderate Evidence
Sample
N=150

What This Study Found

No physical functioning improvements for any group or product type. Spasticity patients using CBD-only products improved in sleep disturbance, fatigue, pain interference, and pain intensity. Spasm patients using balanced, CBD-dominant, or THC-dominant products improved in those same four outcomes. Common adverse events: dry mouth, drowsiness, fatigue, dizziness, nausea.

Key Numbers

150 patients (adverse events), 78 (outcomes). CBD-only improved 4 outcomes for spasticity. Balanced/CBD-dominant/THC-dominant improved 4 outcomes for spasms. Zero physical functioning improvement.

How They Did This

Longitudinal study with patient surveys, clinic records, and PROMIS-29 scores. 150 patients reported adverse events, 78 reported outcomes. Different product types compared.

Why This Research Matters

Conventional spasticity treatments have poor effectiveness or tolerability. Medical cannabis may help manage secondary symptoms even when it does not address the underlying physical impairment.

The Bigger Picture

Medical cannabis may be most useful as an adjunct that improves quality of life around a condition rather than reversing the condition itself.

What This Study Doesn't Tell Us

No control group. Self-reported outcomes. Small outcome sample (n=78). Product types not randomly assigned.

Questions This Raises

  • ?Why did CBD-only work for spasticity but not spasms?
  • ?Would combining cannabis with physical therapy improve functional outcomes?

Trust & Context

Key Stat:
Improvements in sleep, fatigue, pain but zero improvement in physical functioning
Evidence Grade:
Longitudinal design with validated outcomes, but lack of control group limits causal claims.
Study Age:
2026 publication
Original Title:
Investigating the effectiveness and adverse events of medicinal cannabis for patients with muscle spasticity or spasms.
Published In:
The Journal of pharmacology and experimental therapeutics, 393(1), 103780 (2026)
Database ID:
RTHC-08516

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Follows a group of people over time to track how outcomes develop.

What do these levels mean? →

Frequently Asked Questions

Can cannabis treat muscle spasticity?

It did not improve physical functioning, but it did improve related symptoms like pain, sleep, and fatigue that significantly affect quality of life.

Which type of cannabis worked best?

CBD-only for spasticity patients; THC-containing products for spasm patients.

Read More on RethinkTHC

Cite This Study

RTHC-08516·https://rethinkthc.com/research/RTHC-08516

APA

Nastatos, Xenia L; Schubert, Elise A; Wheate, Nial J. (2026). Investigating the effectiveness and adverse events of medicinal cannabis for patients with muscle spasticity or spasms.. The Journal of pharmacology and experimental therapeutics, 393(1), 103780. https://doi.org/10.1016/j.jpet.2025.103780

MLA

Nastatos, Xenia L, et al. "Investigating the effectiveness and adverse events of medicinal cannabis for patients with muscle spasticity or spasms.." The Journal of pharmacology and experimental therapeutics, 2026. https://doi.org/10.1016/j.jpet.2025.103780

RethinkTHC

RethinkTHC Research Database. "Investigating the effectiveness and adverse events of medici..." RTHC-08516. Retrieved from https://rethinkthc.com/research/nastatos-2026-investigating-the-effectiveness-and

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.