Amitriptyline in the treatment of fibromyalgia: a systematic review of its efficacy

The objective of this study was to assess the efficacy and safety of amitriptyline as a treatment of FM. A comprehensive computerized search in Medline (Pubmed), EMBASE and The Cochrane Library was performed. Randomized controlled trials (RCTs) comparing amitriptyline vs placebo in adult patients suffering from FM were identified, the methodological quality was assessed and the results of the main outcomes were evaluated. Ten RCTs were identified. Large clinical variability and statistical heterogeneity precluded quantitative meta-analysis. Overall, the study quality was moderate to high. Amitriptyline 25 mg/day (six RCTs) demonstrated a therapeutic response compared with placebo in the domains of pain, sleep, fatigue and overall patient and investigator impression. This benefit was generally seen at 68 weeks of treatment but no effect was noted at 12 weeks. Amitriptyline 50 mg/day (four RCTs) did not demonstrate a therapeutic effect compared with placebo. Neither dose of amitriptyline had an effect on tender points count. No clear statements on adverse events with amitriptyline can be made due to inconsistencies in data among the studies. A definitive clinical recommendation regarding the efficacy of amitriptyline for FM symptoms cannot be made. There is some evidence to support the short-term efficacy of amitriptyline 25 mg/day in FM. There is no evidence to support the efficacy of amitriptyline at higher doses or for periods 8 weeks. More stringent RCTs with longer follow-up periods are required to determine the long-term efficacy and safety of the amitriptyline and define its role in the multidisciplinary management of FM.