@Nippy , there's been a couple of the Disease Modifying Therapies (DMTs) that have caused hair loss/thinning. Usually, it's a short term side-effect, which recovers well.

Use the Forum Search  (magnifying glass, top right) and search for Hair Loss to locate previous conversations on this subject..

I have been on plegridy for just over a year and I have noticed definite hair thinning 😔 I'm quite self conscious about it but people tell me that they can't notice it. I take biotin every day to try and help but I haven't noticed that  much difference since taking it (but haven't stopped in case it gets worse!).

Does Plegridy cause hair loss?, anyone had any experience ?, thanks