Prednisone must have suppressed my allergy to sulfa????

Hi all--

To summarize: stomach pains / d like none I'd ever experienced before (24 yrs old), etc., led to a colonoscopy which led to a diagnosis of UC which led to my doctor prescribing prednisone (20 mg in the AM / 20 mg in the PM for 10 days, followed by 10 days of just 20 mg in the morning) + sulfasalizine (500 mg in the AM / 500 mg in the PM) for the same 20 days and to be continued (with folic acid).

Stopping prednisone caused me terrible headaches almost immediately, followed in a few days by what I thought was a break out of acne (which I have never had in my life!) and developed over the course of a few more days into a rash all over my body.

Is it possible that the prednisone suppressed my sulfa allergy so it only came through now?

This seems like "the straightest line between two points" (i.e. the easiest, most straightforward explanation), but in my googling it seems like sulfa allergies usually take the form of big horrible hives and usually develop quite quickly, not over days. Not to mention that my doctor was skeptical because when I saw him the rash was contained to my chest and legs so he thought it looks like a clothing/fabric allergy. But then when it spread everywhere I asked him to change my perscriptions.

Has anyone been through this? Are headaches associated with sulfa allergies?

I stopped the sulfasalizine after yesterday morning's dose and only got my replacement (mesalamine) tonight. I think the rash improved slightly since stopping, but now my stomach feels really weird. Could this because I didn't take the sulfa since yesterday morning? Could going off it for 1.5 days already make me feel crappy?

Now I'm itchy everywhere and starving because I'm scared to eat for fear that it will cause a flare-up.

I'm so over all of this... I keep thinking it's done and then one more thing happens.

Any advice is appreciated!

XO