Botulinum Toxin Type A for the Prophylactic Treatment of Chronic Daily Headache: A Randomized, Double-Blind, Placebo-Controlled Trial

Although the primary efficacy end point was not met, all groups responded to treatment. The 225 U and 150 U groups experienced a greater decrease in headache frequency than the placebo group at day 240. The placebo response was higher than expected. BoNTA was safe and well tolerated. Further study of BoNTA prophylactic treatment of CDH appears warranted.