Suggest Remedy For Pain From An Infected Boil

my husband has a boil and was prescribed Keflex and bactrim. He is in alot of pain. he has 2 doses in him of each but he thought he was running a fever and took advil. Should i give it a little while for the meds to kick in or go to the er. He also just finished a 3 day round of decadron for his ms on Wed.