Objective: To assess the efficacy and tolerability of prophylactic drugs for chronic tension-type headache (TTH) in adults.
Methods: We searched several databases from inception to August 2009. We selected randomized trials that reported the effects of prophylactic drugs in patients with TTH, with a pain measure (intensity, frequency, duration, improvement or index) as outcome measure. Two authors independently assessed risk of bias and extracted data from the original reports. A data synthesis was carried out according to the type of medication.
Results: We included 44 trials (3399 patients), of which 15 (34.1%) were considered to be of low risk of bias. Main types of medications studied were antidepressants, muscle relaxants, benzodiazepines and vasodilator agents. Overall, antidepressants were no more effective than placebo, and there were no significant differences between different types of antidepressants. There was conflicting evidence about the effectiveness of benzodiazepines and vasodilator agents compared with placebo. Furthermore, there was limited evidence that propranolol had negative effects on depression in TTH patients, when compared with placebo or biofeedback. There was no evidence concerning the effectiveness of muscle relaxants alone or 5-HT receptor agonist compared with placebo.
Conclusions: Overall, antidepressants were no more effective on headache intensity or frequency and analgesic use than placebo. Propranolol seemed to have negative effects on depression in TTH patients when compared with placebo or biofeedback. No evidence was found for the use of muscle relaxants alone or 5-HT receptor agonist.