Sauna for chronic pain syndrome
Evidence review
Overview
In a Japanese inpatient study of mixed chronic pain, adding daily far-infrared sauna (Waon-style) therapy to multidisciplinary treatment did not clearly improve pain scores beyond multidisciplinary treatment alone, since both groups improved. The sauna group had lower anger scores after treatment and a higher rate of return to work at 2 years. The study is small and the abstract does not report randomization.
Key findings
- Pain VAS improved in both groups; between-group difference in pain behavior p=0.07 (Masuda 2005)
- Return to work at 2 years: 77% (17/22) with added sauna vs 50% (12/24) with multidisciplinary treatment alone, p<0.05 (Masuda 2005)
- Survey of 133 pain-clinic patients who use saunas: heat allodynia or hyperalgesia in 8-15%; 3 of 17 with post-injury nerve pain reported worsening (Nurmikko 1992)
Every study we reviewed
2 mixed results
Each study was checked on PubMed. The colored edge shows the direction of the result. The research library lists 26 studies on chronic pain and musculoskeletal conditions, across all heat and cold therapies, including case reports and older work not graded here.
The effects of repeated thermal therapy for patients with chronic pain.
Masuda A et al. Psychother Psychosom. 2005. PubMed 16088266 · DOI
- Who
- Hospitalized adults with chronic pain (Japan)
- What
- Multidisciplinary treatment (CBT, rehabilitation, exercise) plus far-infrared dry sauna and post-sauna warming once daily vs multidisciplinary treatment alone
- Protocol
- 7/wk · 4 wk
- Measured
- Pain VAS, pain behavior, depression, anger; return to work at 2 years
- Result
- VAS, pain behavior, depression and anger decreased in both groups; pain behavior slightly lower with sauna (p=0.07); anger lower with sauna (p=0.05); return to work 77% vs 50% at 2 years (p<0.05)
- Limitations
- Randomization not reported in abstract; small; no between-group difference shown for pain VAS; heterogeneous pain diagnoses
Effect of exposure to sauna heat on neuropathic and rheumatoid pain.
Nurmikko T et al. Pain. 1992. PubMed 1375727 · DOI
- Who
- Pain clinic patients who bathe in saunas: 61 peripheral neuropathic pain, 13 central pain, 59 rheumatoid pain (Finland)
- What
- Regular Finnish sauna bathing (self-reported experience) with quantitative sensory testing
- Measured
- Heat allodynia/hyperalgesia and pain response to sauna
- Result
- Heat allodynia or hyperalgesia was infrequent: 10% peripheral neuropathic, 15% central and 8% rheumatoid pain; 3 of 17 with post-injury nerve pain reported exacerbation; mechanical allodynia in 48-54% of neuropathic groups
- Limitations
- Self-report; no control group; does not measure therapeutic benefit
Protocols used in the studies
Daily far-infrared dry sauna followed by post-sauna warming for 4 weeks as inpatients, added to multidisciplinary pain treatment; temperature and session length not given in the abstract (related Waon protocols use 140 F for 15 minutes).
What is still unknown
No randomized trial; unknown which chronic pain diagnoses respond, the effective dose, and whether outpatient or home sauna reproduces inpatient results.
Safety
Cautions for sauna in this condition
- General contraindications include unstable angina, recent myocardial infarction and severe aortic stenosis; alcohol during sauna use increases risk of hypotension and arrhythmia (PMID 11165553).
- Heat-evoked pain (heat allodynia/hyperalgesia) was uncommon (8-15%) among chronic neuropathic and rheumatoid pain patients who used saunas, but occurred in some post-injury nerve pain (PMID 1375727).
For clinicians
Suggested rationale
In a controlled inpatient study, adding daily far-infrared sauna to multidisciplinary pain treatment was associated with a higher return-to-work rate at 2 years (77% vs 50%) without a clear difference in pain scores (Masuda 2005); sauna may be considered only as an adjunct within a multidisciplinary plan.
Suggested wording only. The treating clinician decides whether it reflects their clinical judgment for this patient.
Typical ICD-10 codes: G89.4, G89.29. Examples only; the clinician assigns the code.
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