I would take him to the vet. He probably has a yeast infection, or some other kind of infection. The vet will clean his ears in the office and give you medication.
Floppy ears require extra attention to cleaning because the ear canal is more likely to harbor dirt/wax and have less air circulation. After baths, use a cleaner like VetSolutions that has a drying agent in it.
Don't skip the vet visit. An untreated ear infection can lead to other illnesses and hearing loss.
__________________ Kristin, Max and Teddy  |