IRCT20260819070731N1 IRCT 2026-09-08 Tabriz University of Medical Sciences Duloxetine Alone and in Combination with Bupropion in Patients with Fibromyalgia Comparison of the Effects of Duloxetine Alone and in Combination with Bupropion on Cognitive Symptoms and Depression in Patients with Fibromyalgia 2026-09-23 anticipated 40 Recruiting https://irct.ir/trial/92715 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: Using a random number table In this method, each participant in the study is assigned a number (from 1 to 40; depending on the sample size) and a subset of the population is randomly selected using a random number table. Even numbers are assigned to the duloxetine alone group and odd numbers are assigned to the duloxetine plus bupropion group, Blinding description: The study will be conducted in a double-blind manner. Following randomization, bupropion and placebo capsules, which will be identical in appearance, color, packaging, and administration schedule, will be provided to participants in sealed and coded packages for concomitant use with duloxetine. The allocation codes will be maintained by an individual who is independent of the assessment and data collection processes. Neither the participants nor the researcher responsible for clinical assessments and data collection will be aware of the treatment allocation. In addition, the data analyst will remain blinded to the allocation codes until completion of the statistical analysis and finalization of the results. 3 Fibromyalgia. Intervention 1: Intervention group: Treatment with duloxetine (with a dose of 20 to 60 mg per day) + bupropion at a dose of 150 mg per day. Intervention 2: Control group: Treatment with duloxetine alone (with a dose of 20 to 60 mg per day). Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is There is no further information.