I took my first injection yesterday and have had moderate knee pain that never occurred before. I had been off of Rebif for nearly a month and actually felt way better. Now I am in pain that is relieved by prescription Lortab. I also took Copaxone which worked great! I wouldn't have known I even had MS if not for the daily shots. However, I had horrible nausea that caused me to drink ensures everyday and my gastronomy doc told me to stop taking the drug unless I wanted to drink ensures tor the rest of my life. Since Avonex is my third drug choice by docs, I am concerned I will have the same horrible pain since they in the same drug family. Has anyone else had this side effect or other joint pain?