dry rash

Question
Hi I've been to the vet about my dogs rash inside her ears and the vet gave me pills for a bacterial infection she gave me 10 pills and i was to give her 1/2 in morning and 1/2 at night and it cleared it up but after the pills were gone she started scratching and getting the dry rash again she scratches till shes raw and its under her chin as well. I have a boston terrier. If she has an allergy in my home how do i find out what it is. Please help me i have no idea whats wrong with her

Answer
IF the pills were an antibiotic, then there is probably an infection.  If it was a steroid, then it is an allergy.  To test for allergies, a blood test can be done.  If there is still an infection after the pills are gone, the dog may need to continue a low dose antibiotic.