Efficacy of Pregabalin Versus Combined Pregabalin and Milnacipran in Fibromyalgia.

Group 1: will receive pregabalin as a monotherapy. Pregabalin will be administered according to the treatment recommendations for fibromyalgia in the package insert \[Pfizer Inc., 2012\] starting by 50 mg twice daily increasing to 300 mg twice daily according to the efficacy and tolerability for 3 months.

Group 2: will receive a combined pregabalin and milancipran. Pregabalin will be administered as group 1, while milancipran will be administered according to the treatment recommendations for fibromyalgia, starting by 50 mg once daily for 1 week then increased to reach 100 mg daily (50 mg twice daily) based on efficacy and tolerability for 3 month.