Long-term efficacy of spironolactone on pain, mood, and quality of life in women with fibromyalgia: An observational case series.

Objective No single drug is broadly efficacious in the long-term treatment of fibromyalgia syndrome (FMS). Spironolactone is known to ameliorate mood and tension headache or migraine in women with premenstrual syndrome or clinical signs of hyperandrogenism. In a case series of women with treatment resistant FMS spironolactone was therefore added to their medication, and they were observed for at least 12 months. Methods 31 women with treatment-resistant FMS received spironolactone as add-on medication to various pain modulating drugs. 15 women responded to spironolactone and baseline data were compared with assessments over 12-14 months on treatment with spironolactone (ALDACTONE®) in dose range 100-200 mg/day. The efficacy was evaluated by the fibromyalgia impact questionnaire (FIQ) total score and 8 FIQ subtests, a German mood inventory (BSKE-EWL), and further assessments of changes in relevant psychological and physical complaints. 16 women had no effect and stopped the treatment early. Results The subsequent data refer to the 15 responders. The FIQ total score (maximal score = 80) decreased from 56.6 ± 10.0 at baseline to 17.1 ± 11.9 (mean ± SD) 12-14 months later, and pain intensity on an 11 point numeric rating scale (NRS) decreased from 8.8 ± 1.6 to 2.6 ± 1.9 (mean ± SD). Similar changes in FIQ subscores were found for fatigue, morning tiredness, stiffness, anxiety, and depression. Emotional functioning consistently improved: positive mood from 20.0 ± 5.4 to 37.7 ± 5.4 (maximal score = 48), and negative mood from 35.4 ± 5.3 to 10.0 ± 4.4 (maximal score = 60) (each mean ± SD) as well as other mental and physical dysfunctions including non-restorative sleep. All these changes at 4-6 weeks remained on this level for 11-13 months. The drug was well-tolerated and safe, no serious adverse effects were observed. Regular monitoring of serum potassium did not reveal hyperkalemia. All 15 women were able to reduce or discontinue concomitant drugs. Conclusion Fifteen of 31 women with otherwise treatment-resistant FMS experienced a number of prolonged beneficial effects from spironolactone on their complex pain-condition. Implications and discussion We hypothesise that spironolactone affects several central and peripheral neurotransmitter systems such as γ-aminobutyric acid (GABA) activity and dopaminergic transmission. The high rate of non-responsive patients underlines that FMS may represent several subgroups. Pain relief and improvement of associated FHS-symptoms and positive effects on additional diseases or dysfunctions give reasons for marked and sustained improvement in the quality of life. Well-controlled, double-blind, and randomised trials are necessary to confirm our potentially very important observations.