Suggest Treatment For Impetigo

Hi there...i apparently have impetigo, i have had a few little bumps which went away and kept reappearing so after several months finally went to the doctors and impetigo was the diagnosis...i was given an antibiotic ointment which i have been applying as directed but it doesn't seem to be clearing up...i am at the end of the week which i was told to use it for and wondering whether i should continue using it or go back to the doctor for something stronger or should simply stop and give the skin a rest?