Ok, certainly tests were done to establish there is a vasculitis. (Giant cell arteritis would sound like this and methotrexate is one option for it, maybe that is it?). This is not a common condition and there isn t much about it in the literature. The principles underlying the use of methotrexate on an inflammatory/immunological disease are quite sound and it sounds like it is working. Side effects on the methotrexate are quite common and the approach used is the usual approach to toxicity with methotrexate. It all sounds quite reasonable. I don t know about this particular instance, however, in other instances in which methotrexate is used there are two groups of other medications that can be used. One is steroids. Methotrextate is generally safer. The other are antibody injections that have been developed only in recent years. They kill off one particular part of the immune system but not all of the immune system is affected and nothing BUT the immune system is affected. This is why it is safer than steroids. Those are the usual alternatives to methotrexate. I don t know if it is reasonable in your particular condition.