I went off it, and went temporariy off ALL meds and supplements and no alcohol, as all of these things can affect
liver anyzyme levels. After one week,
liver function back to normal. Restarted
Rebif and only Rebif, stayed off the other meds, alcohol, etc, and liver enzymes shot up again after only a weeek or two.
So I stopped and immediately started Copaxone. This was nearly 5 years ago. I've had no side effects other than the inital site reactions and one minor IPIR episode.