The Efficacy and Safety of Pregabalin Combined With Venlafaxine in Patients With Fibromyalgia

In the pregabalin monotherapy group, pregabalin will be initiated at 150 mg daily, divided into 2 or 3 doses per day, and increased to 300 mg per day after 3 to 7 days, subsequent increases of 150 mg daily may occur every 3 to 7 days, based on individual patient response and tolerability, with a maximum dose of 600 mg daily.

In the pregabalin with venlafaxine group, the dose titration of pregabalin is identical with pregabalin monotherapy group. Venlafaxine will be administered at 75 mg daily with breakfast initially. If the initial dose is well-tolerated, the dose could be further escalated by 75 mg per day after 4 days, up to a maximum of 225 mg per day. With each dose increase, AEs will be assessed and categorized as mild, moderate, or severe. If participants tolerate the current dose for 2 to 3 days, it will be maintained, with the expectation that tolerance to AEs will develop. If AEs become intolerable, the dose will be decreased back to the previous dose, which was defined as the maximum tolerated dose. In the combination group, dose titration of both pregabalin and desvenlafaxine will be conducted simultaneously. If AEs occur, the next dose regimen should be determined in consultation with a clinical physician.