Well I had my appt on the 18th and my MRI had little to no change since 2 years ago

. So he want to put me on Avonex. He said that it was my choice to go on the Copaxone or Betasaron but he recomands the avonex because I have had little change. I go back on the 15 of June to let him know what I want to go on.
He told my hubby that if he sees that I am getting depressed to call him right away he he would get me back on the prozac that I have been on many times before.
So my question now is how is Avonex? and is there anything that I should be worried about?