Cannabis Use in MS Patients Linked to Higher Pain and Fatigue the Next Day

Daily ecological momentary assessments in people with MS found that cannabis use predicted greater fatigue and higher momentary pain the following day, despite patients likely using cannabis to manage these very symptoms.

Kim, Jeeyeon et al.·Archives of physical medicine and rehabilitation·2026·Moderate Evidencelongitudinal
RTHC-08385LongitudinalModerate Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
longitudinal
Evidence
Moderate Evidence
Sample
N=258

What This Study Found

Cannabis use was associated with greater subsequent fatigue and higher momentary pain in MS patients, while alcohol and nicotine also predicted greater fatigue. In the reverse direction, higher average pain predicted reduced alcohol use and increased opioid use, revealing complex bidirectional symptom-substance dynamics.

Key Numbers

N=258; 14-day EMA periods at 3 timepoints; cannabis→increased fatigue; cannabis→increased momentary pain; caffeine→reduced fatigue; alcohol→reduced stress; opioids→increased average pain; bidirectional symptom-substance relationships

How They Did This

Secondary analysis of ecological momentary assessment data collected 4 times daily for 14 days at baseline, 1-year, and 2-year follow-ups from 258 ambulatory adults with MS, using mixed-effects logistic regression for lagged associations.

Why This Research Matters

Many MS patients use cannabis for symptom management, but this study reveals a paradox: cannabis may actually worsen the very symptoms (pain, fatigue) it's intended to treat, creating a self-reinforcing cycle.

The Bigger Picture

The finding that cannabis worsens next-day pain and fatigue in MS challenges its perceived therapeutic value in this population and has important implications for neurologist counseling.

What This Study Doesn't Tell Us

Secondary analysis; EMA self-report; dichotomous substance use (yes/no) misses dose information; 14-day windows may not capture longer patterns; ambulatory patients may not represent all MS severity levels; cannot rule out confounding by flare severity.

Questions This Raises

  • ?Is the pain-worsening effect from cannabis rebound or from cannabis-related sleep disruption?
  • ?Would CBD-only products show different effects?
  • ?Should neurologists actively counsel against cannabis for MS symptom management?

Trust & Context

Key Stat:
Evidence Grade:
Well-designed EMA study with repeated within-person measurements and appropriate lagged analysis, providing granular daily evidence despite limitations of self-report and dichotomous substance measurement.
Study Age:
Published 2026; multi-year EMA follow-up.
Original Title:
Daily Temporal Associations Between Use of Psychoactive Substances and Fatigue, Pain, Stress, and Depressive Symptoms in People with Multiple Sclerosis.
Published In:
Archives of physical medicine and rehabilitation (2026)
Database ID:
RTHC-08385

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

Does cannabis help with MS symptoms?

This daily-tracking study found the opposite — cannabis use predicted greater fatigue and higher pain the next day in people with MS, suggesting it may paradoxically worsen the symptoms patients use it to manage.

What substances affect MS symptoms most?

Cannabis was linked to worse pain and fatigue, while caffeine reduced fatigue. Alcohol reduced stress but increased fatigue. These daily patterns suggest MS patients need personalized guidance on substance use and symptom management.

Read More on RethinkTHC

Cite This Study

RTHC-08385·https://rethinkthc.com/research/RTHC-08385

APA

Kim, Jeeyeon; Ehde, Dawn M; Alschuler, Kevin N; Fritz, Nora E; Kratz, Anna L. (2026). Daily Temporal Associations Between Use of Psychoactive Substances and Fatigue, Pain, Stress, and Depressive Symptoms in People with Multiple Sclerosis.. Archives of physical medicine and rehabilitation. https://doi.org/10.1016/j.apmr.2026.01.014

MLA

Kim, Jeeyeon, et al. "Daily Temporal Associations Between Use of Psychoactive Substances and Fatigue, Pain, Stress, and Depressive Symptoms in People with Multiple Sclerosis.." Archives of physical medicine and rehabilitation, 2026. https://doi.org/10.1016/j.apmr.2026.01.014

RethinkTHC

RethinkTHC Research Database. "Daily Temporal Associations Between Use of Psychoactive Subs..." RTHC-08385. Retrieved from https://rethinkthc.com/research/kim-2026-daily-temporal-associations-between

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.