There are those times where this is not always true. Some infections are very resistant to treatment with the usual protocol. When this is a possibility, it is very important to culture the infection and run a sensitivity test to find out what exactly is the organism causing the problem and what specific medication will be needed to correctly treat the problem.
Because the culture and sensitivity can take a period of 5-7 days to come back and sometimes longer, it is important to be very aggressive in treatment of ear infections. It is sometimes important to culture at the beginning of treatment so that we may know the exact cause as soon as possible. Some infections may take 3-6 weeks to clear up if not longer. What ever the case may be, follow the directions of treatment very carefully. Every situation is different, and the period of treatment can take a long time if protocol is not followed. It is also important to clean your pets ears regularly with proper cleaning solution and if treating an infection, the ears should be cleaned twice a day till the infection is cleared.
We would be happy to discuss this further with you at your convenience.