Hi and welcome to Just Answer,
How long has it been there?
How long ago was it seen by your vet?
Is it enlarging or spreading?
Obviously it was not a bug bite which should have resolved itself in just a few days. When I think of oozing lesions on the nose I think of bacterial infections, immune diseases, and fungal diseases. In general, topical products don't penetrate enough to be very effective for these conditions. Unfortunately, these are all treated quite differently and an accurate diagnosis is the first step. Diagnosis can be aided with an impression smear of the ooze, or a punch biopsy of the skin which is submitted to a veterinary pathologist. I would advise returning to your vet and having this worked up further to determine the actual cause of the disease.
Well you didn't really tell me anything I didn't already know or think about. For a dog I always think once to the vet is enough. You know how costly it is. You pay just to walk in the door. Thanks anyways.