I took lysteda last month for the first time. 2 pills three X a day for 3 days. Worked great-very light period. My problems have occurred since then. First, my next period was 6 days late. Second, two days before my late period started, I began to experience severe pain and swelling in all joints-shoulder, elbow, ankle, knee, wrists. So sore I can barely walk without 3 Advil in me. I will be seeing a dr Monday who wants to look at rapid onset rheumatoid arthritis but I'm wondering if it is related to lysteda. Any insight would be appreciated- just wondering if this has happened to anyone else?