Drug prescription strategies in the treatment of patients with fibromyalgia.

OBJECTIVE To analyze prescription strategies followed by rheumatologist specialized in FM treatment. METHODS A prospective, multicentric, 3-month follow-up study with two visits. The drug treatment was started following usual clinical practice conditions. Prescription of benzodiazepines, hypnotics, anticonvulsants and antidepressants were those mainly studied. Clinical evaluation was performed by the ICAF (Combined index of affection in patients with fibromyalgia) questionnaire. The most frequent strategies and their size effect were calculated. RESULTS A total of 232 patients attending 15 rheumatology centers were included. The introduction of an anticonvulsant or an antidepressant were the most common drug strategies followed in 17.7% and 14.7% of patients, respectively. Both strategies produced a statistically significant clinical improvement. The most effective strategy (with an effect size of nearly 1) was the introduction of both drugs (6.5% patients), which increased the antidepressants effect size in 50% and 100% for anticonvulsants. The strategy of no change in the number of drug prescriptions was the most frequent (35.8% patients) but no significant clinical improvement was found in these patients. Some other strategies were very uncommon and have not been analyzed in this study. CONCLUSION The introduction of anticonvulsants or antidepressants, in an isolated or combined form, produces a significant clinical improvement in FM patients. The most effective drug strategy is the introduction of both drugs at the same time. The least effective strategy is not to change the number of drug prescriptions.