My husband had a sore on foot appear to be spider bite ,swollen, red & pus, went to Dr agreed with spider bite , gave him Zpac no lab taken . Sore healed . But is having these sores break out on his hand, leg , neck, & Buttocks . Went back to Dr today didn t think it was staph , didn t take his blood, but placed him on Bactrim160mg to take bid two each time ! What to think?