sulfa allergy and flomax

I (22F) have a sulfa allergy.

when I passed my first kidney stone, I was prescribed flomax (Tamsulosin) like many others on this subreddit. I just learned today that Tamsulosin is actually a sulfa drug. But, non-antibiotic sulfa drugs are chemically different from sulfa antibiotics and are believed to only very rarely cause allergic reactions in those with sulfa allergies. the makers of flomax have a warning about this risk, but the cases of allergic reaction are so rare and understudied that the actual risk of reaction is deemed insufficient to completely avoid prescribing flomax to those with sulfa allergies. when I first used Tamsulosin, I was miserable. While it helped me pass my stone, I experienced severe UTI symptoms like urgency, irritation, aching in the groin area, and burning while urinating. not to mention near fainting everytime I stood up. I understood that these were typical symptoms of both kidney stones and flomax use, but I still felt miserable and avoided taking flomax unless I was in the worst of pain.

fast forward to last Monday. I went into surgery for my first (and hopefully last) laser lithotripsy to break up a 10mm stone in my right kidney. unfortunately, my ureter was not dilated enough to perform the procedure, so they placed a stent. my stent symptoms have been typical and manageable with medication (pyridium and oxybutynin) every 6-8 hours. when I ran out of my meds and my symptoms started coming back, I started taking Tamsulosin again (I was prescribed it but avoided it due to the side effects I had previously had on it). less than 24 hours after my first dose of Tamsulosin, I started experiencing extreme itchiness and burning in my nether regions. the girlies know the feeling. many possibilities ran through my brain: my stent was irritating me, I had a UTI, I had a yeast infection, my laundry detergent was irritating me, I had pinworms… everything. I took a shower, wore loose clothing, and chugged my water, but the irritation persisted. It was hard to focus on anything.

worried I might have a UTI I called my urologist’s office and spoke to the on-call nurse. she said it’s probably just my stent irritating me and refilled my prescriptions (bless). she called again to checkup on me. I confessed the irritation spread to my anus (gotta be real) and she said she’ll let my doctor know. a few minutes later she called me again. she confirmed I had a sulfa allergy. this is when she told me she just remembered the very rare case of allergic reactions to non-antibiotic sulfa drugs. told me to stop taking the Tamsulosin and see if it gets any better.

and here we are. I’m still itchy, but not as bad. hoping that flomax actually is the culprit and wondering if my first bad experience with the drug was actually an allergic reaction. there isn’t much evidence supporting if and why these cases occur.

sooo I’m just curious… anyone else here allergic to sulfa? any weird symptoms on flomax? am I just crazy? why do I have the worst luck with my health? let me know!