I'm not familiar with sulfasalazine, so can't help you a lot, BUT you should know that many Lupus patients are allergic to sulfa-based medications. I don't know that sulfasalazine is sulfa-based, but the name certainly makes it sound like it is!
I found this reference, www.webmd.com/drugs/2/drug-6260/sulfasalazine-oral/details
which says it is most often used for ulcerative colitis, Crohn's disease, and rheumatoid arthritis.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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