Hi L Have A Bacterial Infection, In My Left Breast.

Hi l have a bacterial infection, in my left breast. I was prescribed SMZ-TMP, DS 800-160 mg tab. I’m to take one tablet, two times a day. I’ve been on this medication since Friday. Saturday I noticed that I had developed red blotches on my arms, back, buttock, both breast. I’m also itching, a lot. I’ve increased my water intake. I’m concerned so I didn’t take the nighttime doseage. I’m going to urgent care first thing. Just would like confirmation that I’m handling this correctly. Thank you.
Lynette Kelsey