I had a very very rare but serious reaction to the antibiotic Bactrim. I ended up in an isolation room in the hospital for over a week because my white blood cells and in particular the neutrophils went down to zero. I had no immunity to anything and I am recovering at home now but everyone wears a mask when they come in and when I go out I wear one. My question which I will ask my doctor when I see him next, but since Bactrim is a sulfa drug do I need to avoid ALL sulfa drugs. I need to get a medical alert bracelet to identify my allergy but wondering if it is just one drug specific or the whole class. Thanks