I have the same question. I was taking Avonex. I wanted to take LDN and my neuro said he was fine with taking both. I had read where, pharmacologically speaking, they were incompatible. My neuro said there was no science to base this theory on. After taking both for a while, I could tell no difference with the LDN. I stopped the LDN. Then some months later I stopped the Avonex and started LDN again. I wanted to continue LDN. I went to a new neuro who suggested Gilenya. I really want to be on an FDA approved MS medication and didn't want to switch to Copaxone because of the daily injections. My new neuro suggested Gilenya. I am about to go on it, but haven't seen any info on taking both Gilenya and LDN. I will call the Gilenya phone line, but I was interested if anyone else knows anything. Thanks.