After investigating the side effects of Ocrevus, I discovered this site, so thanks! I just started Ocrevus in February and within days I noticed a cold sore(a bad one) coming on within a week of finishing both starter infusions and also developed chronic low back pain within a week as I've never had before. I decided to look up possible side effects and couldn't believe how spot-on these two side effects were. Never would have guessed low back pain. I've lost some time at work as a result and thought it would clear up eventually, but it is chronic now, though mostly manageable. Just by coincidence, I happened to get the Shingles vaccine a month or so earlier...... and then saw that this is another common side effect. Yikes! Getting Shingles would have been awful. So fortunate. I was previously on Gilenya and did really well on this for several years. My white cell count remained too low, so Doc said time to switch.......But that was a great Med with very few to no side effects. I would have insisted staying on it had it not been for the white cell count issue. Prior to that, I was on Rebif for several years and had the flu-like side effects, so I'd have to say that was my least favorite, though it did it's job preventing flare-ups.