Sauna for fibromyalgia
Evidence review
Overview
Randomized trials of mild water-filtered infrared whole-body hyperthermia, a clinic-delivered form of systemic heat, reduced fibromyalgia pain versus multimodal rehabilitation alone and versus sham hyperthermia; in the sham-controlled trial the difference was significant at weeks 4 and 30 but not at week 12, and responder rates did not differ. The only controlled sauna study is small and non-randomized: 12 mild sauna baths raised pressure pain thresholds by 22% versus 8% with exercise-pool sessions. Waon (140 F far-infrared sauna), sauna-plus-aquatic-exercise and hot-water immersion studies also report pain and FIQ improvements, but these were uncontrolled and small (8-44 patients). Sauna-specific randomized data are lacking.
Key findings
- Sham-controlled RCT, n=41: 6 sessions of mild whole-body hyperthermia over 3 weeks lowered pain by 1.7 vs 0.5 points (0-10) at week 4 (p=0.015) and differed from sham at week 30 (p=0.002), but not at week 12; >=30% responders 10 vs 4 (p=0.13) (Langhorst 2023)
- RCT, n=139: whole-body hyperthermia added to inpatient rehabilitation improved affective (p<0.001) and sensory (p=0.001) pain vs rehabilitation alone; effect sizes 0.41-0.75; transient side effects in 20% (Brockow 2007)
- Controlled, non-randomized, n=18 women: 12 mild sauna baths twice weekly raised tender-point pressure pain threshold by 22% (significant) vs a non-significant 8% with exercise-pool sessions (Piso 2001)
- Waon therapy, uncontrolled, n=13 (8 with secondary fibromyalgia, daily home warm baths as well): pain VAS 6.9 to 3.3 after 10 sessions and FIQ 44.8 to 29.3 (Matsushita 2008)
- Sauna 3 days/week plus underwater exercise 2 days/week for 12 weeks, uncontrolled, n=44: pain and symptoms fell 31-77%, sustained 28-68% at 6 months (Matsumoto 2011)
- Hot-water immersion at 105 F, 45 min 3x/week for 4 weeks, uncontrolled pilot, 8 completers: average pain 5.375 to 3.750 (p=.013) and FIQ-R 60.9 to 37.0; inflammatory markers unchanged (Chadwick 2025)
- Within the hyperthermia RCT arm, longer core-temperature plateau phases showed only a non-significant trend toward lower pain at week 12 (p=0.093) (Öznur 2023)
Every study we reviewed
6 found benefit · 2 mixed results
Each study was checked on PubMed. The colored edge shows the direction of the result. The research library lists 24 studies on fibromyalgia, across all heat and cold therapies, including case reports and older work not graded here.
Mild Water-Filtered Infrared-A Whole-Body Hyperthermia Reduces Pain in Patients with Fibromyalgia Syndrome-A Randomized Sham-Controlled Trial.
Langhorst J et al. J Clin Med. 2023. PubMed 37109279 · DOI · Free full text
- Who
- Adults 18-70 with medically confirmed fibromyalgia (Germany), outpatients
- What
- Mild water-filtered infrared-A whole-body hyperthermia vs sham (insulating foil blocking radiation)
- Protocol
- 101.7 core (mean max) °F · 60 (about 45 heating, 15 at plateau) + about 30 rest min · 2/wk · 3 wk
- Measured
- Pain intensity (Brief Pain Inventory) at week 4
- Result
- BPI pain intensity at week 4 (primary): -1.7 points (-30.7%) with hyperthermia vs -0.5 (-9.5%) with sham, between-group p=0.015 (ANCOVA, two-sided); >=30% responders 10 vs 4 (p=0.13). Week 30: -0.9 vs +0.5 points (p=0.002); the week-12 difference was not significant (reported in PMID 38001951). Side effects with hyperthermia: skin burning sensation 15 of 21 (71.4%), palpitations/heat stress 8 (38.1%), headache 5 (23.8%; sham 4 of 20), severe circulatory problems 2 (9.5%), dizziness 2; one patient needed an infusion; none stopped treatment.
- Limitations
- Small (21 vs 20); single-blind (therapists not blinded) and the sham was more often recognized (100% of the active group vs 80% of controls believed they had active treatment); responder rates and week-12 pain did not differ; hyperthermia device, not sauna.
A randomized controlled trial on the effectiveness of mild water-filtered near infrared whole-body hyperthermia as an adjunct to a standard multimodal rehabilitation in the treatment of fibromyalgia.
Brockow T et al. Clin J Pain. 2007. PubMed 17277647 · DOI
- Who
- Inpatients meeting ACR 1990 fibromyalgia criteria in German rehabilitation hospital
- What
- Mild water-filtered near-infrared whole-body hyperthermia plus multimodal rehabilitation vs rehabilitation alone
- Protocol
- 100.6 core °F · 15 at target min · 2/wk · 3 wk
- Measured
- Affective and sensory pain (McGill), through 6 months
- Result
- Significant group differences favoring hyperthermia: affective pain p<0.001, sensory pain p=0.001; moderate effect sizes 0.41-0.75 across outcomes; side effects in 14/69 (20%), all resolved within 30 min
- Limitations
- Not sham-controlled; adjunct to inpatient rehabilitation; hyperthermia device, not sauna
[Whole body hyperthermia in pain therapy. A controlled trial on patients with fibromyalgia].
Walz J et al. Schmerz. 2013. PubMed 23354314 · DOI
- Who
- Fibromyalgia patients in a German rehabilitation clinic
- What
- Mild near-infrared whole-body hyperthermia once or twice weekly added to multimodal rehabilitation vs rehabilitation alone
- Protocol
- 1-2/wk · 3 wk
- Measured
- Pain intensity at discharge and 6 months
- Result
- Once-weekly hyperthermia was significantly better than twice-weekly hyperthermia and control for pain reduction and affective pain; twice weekly was not superior to control
- Limitations
- Three-arm controlled trial, randomization not stated in abstract; German-language; no dose-response (once weekly beat twice weekly)
Efficacy of Waon therapy for fibromyalgia.
Matsushita K et al. Intern Med. 2008. PubMed 18703857 · DOI · Free full text
- Who
- 13 women meeting ACR fibromyalgia criteria (Japan); 8 had fibromyalgia secondary to an autoimmune disease (e.g. lupus, rheumatoid arthritis, Sjogren) and 8 took low-dose prednisolone
- What
- Waon therapy: far-infrared dry sauna then 30 min wrapped in blanket
- Protocol
- 140 °F · 15 (+30 min warm rest) min · 2-5/wk
- Measured
- Pain VAS, FIQ
- Result
- Pain VAS 6.9 before, 4.2 after the first session, 3.3 after the 10th and 3.9 at follow-up (median 14 months); pain fell by 20-78% after 10 treatments; FIQ 44.8 to 29.3 (p=0.006, 10 of 13 completed); all 10 sessions completed without significant side effects.
- Limitations
- Uncontrolled; 13 patients, most with secondary fibromyalgia; daily home hot baths as a co-intervention; no blinding.
Effects of thermal therapy combining sauna therapy and underwater exercise in patients with fibromyalgia.
Matsumoto S et al. Complement Ther Clin Pract. 2011. PubMed 21742283 · DOI
- Who
- Women meeting ACR fibromyalgia criteria (Japan)
- What
- 12-week program: sauna 3 days/week plus underwater exercise 2 days/week
- Protocol
- 3/wk · 12 wk
- Measured
- Pain VAS, FIQ, SF-36
- Result
- Pain and symptom reductions of 31-77% after 12 weeks, remaining 28-68% during 6-month follow-up; SF-36 improved
- Limitations
- Uncontrolled; combined with exercise so sauna effect cannot be isolated
The impact of a heat therapy intervention on pain and fibromyalgia symptoms in patients with fibromyalgia: a pilot study.
Chadwick AL et al. Front Pain Res (Lausanne). 2025. PubMed 40182803 · DOI · Free full text
- Who
- Sedentary women aged 18-65 meeting ACR 2016 fibromyalgia criteria (United States); 13 enrolled, 11 started, 8 completed
- What
- Hot-water immersion, 45 min, 3 times weekly for 4 weeks
- Protocol
- 105 (water) °F · 45 min · 3/wk · 4 wk
- Measured
- Pain NRS, fibromyalgia impact, physical function, sleep, quantitative sensory testing, heat shock proteins, inflammatory markers
- Result
- In 8 completers: BPI average pain 5.375 to 3.750 (p=.013); BPI worst pain 8.250 to 6.125 (p=.035); FIQ-R 60.9 to 37.0 (p=.008 in the table, p=.035 in the text); PROMIS physical function and sleep impairment improved; no change in depression, anxiety, sensory testing or inflammatory markers. No safety issues.
- Limitations
- Non-randomized single-arm pilot with no power calculation; 8 of 11 starters completed (1 withdrew for unrelated health issues, 2 stopped by COVID-19); reporting inconsistencies (FIQ-R p value; some figures say n=6); hot-water immersion, not sauna.
Investigating the Influential Factors of Mild Water-Filtered Infrared-A Whole-Body Hyperthermia for Pain Relief in Fibromyalgia: A Mixed-Methods Approach Focusing on Predictors and Patient Perspectives.
Öznur Ö et al. Biomedicines. 2023. PubMed 38001951 · DOI · Free full text
- Who
- Patients with fibromyalgia treated within a randomized trial of mild whole-body hyperthermia (Germany)
- What
- Mild water-filtered infrared-A whole-body hyperthermia, 6 sessions over 3 weeks (clinic device, not a sauna)
- Protocol
- 101.3 core (target) °F · 60 (about 15 at plateau) + about 30 rest min · 2/wk · 3 wk
- Measured
- Predictors of pain intensity at week 12; patient interviews
- Result
- In 20 intervention-arm patients, baseline pain predicted week-12 pain (beta 0.63, p=0.002); longer plateau phase showed a non-significant trend toward lower pain (beta -0.30, p=0.093); model R2 0.546. All 10 interviewed patients reported improvement at some point, but by the week-12 interview pain had returned to pre-treatment levels in most.
- Limitations
- Secondary analysis of one arm of a randomized trial (PMID 37109279), not a cohort; small; the parent trial found no between-group pain difference at week 12; hyperthermia device, not sauna.
Analgesic effects of sauna in fibromyalgia
Piso U et al. Physikalische Medizin, Rehabilitationsmedizin, Kurortmedizin. 2001. Not in PubMed: source · DOIGerman publication; title and summary translated by SaunaLMN. Original title: Analgetische Wirkungen der Sauna bei der Fibromyalgie
- Who
- Women with primary fibromyalgia (ACR criteria), Germany; plus a questionnaire of 18 further patients who had received sauna and other physical therapies
- What
- Mild sauna baths, 12 sessions twice weekly (n=9) vs 12 exercise-pool sessions twice weekly (n=9)
- Protocol
- 2/wk · 6 wk
- Measured
- Pressure pain threshold at ACR tender points (algometer); patient questionnaire
- Result
- Pressure pain threshold rose by a mean 22% after the sauna series (significant vs baseline; p<0.05 after the 6th and 12th baths) vs a non-significant 8% with exercise-pool sessions; in the questionnaire, 10 of 18 patients reported pain relief from sauna, more often than from warm packs (7 of 16), physiotherapy (6 of 16), exercise pool (7 of 18) or massage (6 of 15)
- Limitations
- Allocation not described as randomized; 9 women per group; pressure-pain threshold rather than a clinical pain score; within-group tests only; sauna dose not reported; German-language article (English abstract also published)
Protocols used in the studies
Waon studies used a 140 F (60 C) far-infrared sauna for 15 minutes followed by 30 minutes of warm rest, 2-5 days/week for 10 sessions; a German controlled study used 12 mild sauna baths twice weekly (temperature not reported); one program combined sauna 3 days/week with aquatic exercise for 12 weeks; a hot-water immersion pilot used 105 F (40.5 C) water for 45 minutes 3 times weekly for 4 weeks, holding rectal temperature at 101.3-102.2 F. Randomized trials used clinic hyperthermia devices with 60-minute sessions (about 45 minutes heating, then about 15 minutes at a core temperature of about 100.6-101.7 F, 38.1-38.7 C), twice weekly for 3 weeks (6 sessions).
What is still unknown
No randomized trial of home or clinic sauna (as opposed to hyperthermia devices) in fibromyalgia; the one controlled sauna study measured pain thresholds rather than clinical pain; optimal frequency is unclear (once weekly outperformed twice weekly in one trial); durability beyond 6-7 months unknown.
Safety
Cautions for sauna in this condition
- In the sham-controlled hyperthermia trial, side effects were common in the active group: skin burning sensation 71.4%, palpitations or heat stress 38.1%, headache 23.8% and severe circulatory problems 9.5%; one patient needed an intravenous infusion after severe dizziness, but none stopped treatment (PMID 37109279).
- Transient side effects occurred in 20% of patients receiving whole-body hyperthermia as an adjunct to rehabilitation and resolved within 30 minutes (PMID 17277647).
- Next-day exacerbation of pain after sauna is described as most obvious in fibromyalgia and in women, and is attributed to inadequate cooling (PMID 3265298).
- General contraindications include unstable angina, recent myocardial infarction and severe aortic stenosis; avoid alcohol (PMID 11165553).
For clinicians
Suggested rationale
Randomized trials show that mild whole-body heat reduces fibromyalgia pain versus sham at the end of treatment (Langhorst 2023) and as an adjunct to rehabilitation (Brockow 2007), and smaller sauna studies report raised pain thresholds after 12 mild sauna baths (Piso 2001) and pain reduction with a 140 F far-infrared sauna (Matsushita 2008); regular sauna can reasonably be considered as an adjunct to exercise-based fibromyalgia care, recognizing that the benefit in the sham-controlled trial was not sustained at every follow-up.
Suggested wording only. The treating clinician decides whether it reflects their clinical judgment for this patient.
Typical ICD-10 codes: M79.7. Examples only; the clinician assigns the code.
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