Mirtazapine in treatment of fibromyalgia
Näytönastekatsaukset
3.3.2026
Level of evidence: C
Mirtazapine may have little or no impact on fibromyalgia symptoms and fibromyalgia-related pain.
A Cochrane review on mirtazapine found a limited impact on fibromyalgia symptoms and pain «Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pai»1. The largest trial from Japan had most of the patient and found about 9% relative decrease in fibromyalgia symptoms and pain «Welsch P, Bernardy K, Derry S, et al. Mirtazapine for fibromyalgia in adults. Cochrane Database Syst Rev 2018;8(8):CD012708 »2.
Mirtazapine increased the risk of somnolence (RD 24%), weight gain (RD 13%), and elevated alanine aminotransferase (RD 13%).
We downgraded the evidence due to indirectness (most patients were from Japan and under 64 years of age) and imprecision.
| Reference | Study type | Population | Intervention and comparison | Outcomes | Risk of bias |
|---|---|---|---|---|---|
| RCT=randomized controlled trial; SR=systematic review; MA=meta-analysis; JFIQ = Japanese version of Fibromyalgia Impact Questionnaire; BDI = Beck Depression Inventory | |||||
| «Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pai»1 | RCT | Adults under 64 years old | Mirtazapine 30 mg once daily vs placebo | NRS, JFIQ | low |
| «Welsch P, Bernardy K, Derry S, et al. Mirtazapine for fibromyalgia in adults. Cochrane Database Syst Rev 2018;8(8):CD012708 »2 | SR/MA | Adult with fibromyalgia | Mirtazapine 15-30mg vs placebo | NRS, VAS, BDI, Adverse events | moderate |
| Reference | Comments |
|---|---|
| «Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pai»1 | About 11% dropout rate. Randomization and blinding ok. |
| «Welsch P, Bernardy K, Derry S, et al. Mirtazapine for fibromyalgia in adults. Cochrane Database Syst Rev 2018;8(8):CD012708 »2 | The largest study (1) was low risk of bias, but others had high risk of due to incomplete outcome data and selective reporting. Reported adverse events: Somnolence, weight gain, elevated alanine aminotransferase |
| Reference | Number of studies and number of patients (I/C) | Follow-up time | Mean change from baseline (sd) I | Mean at follow up C | Mean difference (95% CI) |
|---|---|---|---|---|---|
| Level of evidence: low The quality of evidence is downgraded due to indirectness and imprecision. The only low risk of bias study including most of the patients was conducted in Japan on patients under 64 years old. *calculated from the mean at follow up in placebo group | |||||
| «Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pai»1 | 211/211 | 12 weeks | -1,61 (0,10) | -1,17 (0,10) | -0,44 (-0,72 to -0,17) relative decrease -9% (-15% to -4%)* |
| «Welsch P, Bernardy K, Derry S, et al. Mirtazapine for fibromyalgia in adults. Cochrane Database Syst Rev 2018;8(8):CD012708 »2 | 4 studies (326/265) | 7-14 weeks | - | - | SMD – 0,29 (-0,46 to -0,13) |
| Reference | Number of studies and number of patients (I/C) | Follow-up time | Mean change from baseline (sd) I | Mean at follow up C | Mean difference (95% CI) |
|---|---|---|---|---|---|
| Level of evidence: low The quality of evidence is downgraded due to indirectness and imprecision. The only low risk of bias study including most of the patients was conducted in Japan on patients under 64 years old. *calculated from the mean at follow up in placebo group | |||||
| «Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pai»1 | 211/211 | 12 weeks | -12,93 | -9,29 | -3,64 (p-value 0.01) relative decrease -9%* |
References
- Miki K, Murakami M, Oka H, et al. Efficacy of mirtazapine for the treatment of fibromyalgia without concomitant depression: a randomized, double-blind, placebo-controlled phase IIa study in Japan. Pain 2016;157(9):2089-2096 «PMID: 27218868»PubMed
- Welsch P, Bernardy K, Derry S, et al. Mirtazapine for fibromyalgia in adults. Cochrane Database Syst Rev 2018;8(8):CD012708 «PMID: 30080242»PubMed