IRCT20191231045964N1 IRCT 2020-08-15 Ahvaz University of Medical Sciences Melatonin in rheumatoid arthritis Survey the effect of melatonin supplementation on clinical symptoms and sleep quality in patients with rheumatoid arthritis 2020-05-04 anticipated 70 Complete https://irct.ir/trial/45095 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Randomization description: The block randomization technique with 1:1 ratio will be used to achieve balanced group sizes. Supplements and placebos are in the same packaging. Only the code is written on the packages. Patients and researchers do not know the type of intervention and after analyzing the data, packet codes are decoded, Blinding description: Participants, investigators or the assessors of the outcomes are unaware of the study groups. 3 Rheumatoid arthritis. Intervention 1: Intervention group: One 3 mg melatonin capsule, daily, for 2 months. Intervention 2: Control group: One 3 mg placebo capsule, daily, for 2 months. 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 Its release schedule is not yet known