Advice on whether to tell my new employers I have MS

Hi I’d like to ask peoples thoughts on whether I should tell my emploers I have MS. I started a new job 2 weeks ago and my employers never asked about any disability or health isuues. As you can guess I don’t look like I have MS but I feel like I do! They have asked me to fill in a medications form just in case anything happens to me while I’m in the office. I take pregabalin and Copaxone. Should I tell them now, wait until I have finished my 6 month probabtion period or not tell them unless I have a relapse (which I course is not goin gto happen! - power of positive thought and all that)