I have what I believe is a brown recluse spider bite on my right shoulder next to my armpit. This happened early Friday morning. I developed a bright red rash like a really bad sunburn Friday night all over my body. I went to the ER Saturday because I was dizzy, had nausea, and red. They prescribed meds for allergic reaction. It started to lesson in redness but this morning. It was just as bright red and has stayed that way all day. I now have purplish spots on my stomach and what look to be blisters on the left side of my stomach.
Hi, As the rash has started to lessen you should continue taking the anti-allergic medicine and if possible discuss with your doctor about taking a steroid shot. It can help in improvement of the symptoms faster.  A change is color can occur as the rash will gradually continue to subside so do not worry about it. Along with it do cool compresses or ice packs over the rashes.  Apply Calamine lotion or Ben Chat Doctor.  If there is an eruption of any new symptoms you should consult your Physician soon.  Hope I have answered your query. Let me know if I can assist you further.