In this double blind clinical trial 92 patients suffering from rheumatoid arthritis are
included. Those with the history of intraocular and corneal surgery, diabetic and heavy
smokers are excluded from the study. Before starting the treatment all patients undergo
complete ophthalmic exam, corneal biomechanical properties assessment by Ocular Response
Analyzer (ORA) and corneal thickness measurement. Patients are randomly assigned to treatment
and placebo groups. Those in the treatment groups receive glucosamine sulfate 1500 mg three
times a day. Those in placebo arm receive alike capsule with the same schedule. At month 3
and 6 IOP(intraocular pressure), ORA and pachymetry would be checked again.