I have rheumatoid arthritis. I started Enbrel, 3 weeks ago. I inject it once weekly. I chose to inject on Friday evenings. I have literally slept through the weekends and feel so fatigued. I went to Enbrel's website and it states that extreme tiredness is a serious side effect. I contacted my rheumatologist. He wants me to hold off the medicine, today, and see if this fatigue continues throughout the week. He thinks there is something else causing my symptom. My labs continue to show that my CRP is high. C-reactive protein (CRP) is a substance produced by the liver in response to inflammation. RA-induced inflammation occurs because your immune system mistakes your joints for an invader and persists. Has anyone tried Enbrel or is currently using it? Does anyone else feel like they could sleep for a week?