If your dog suffers from frequent ear irritations or infections, he needs diagnosis and treatment. Your vet is likely to prescribe antibiotics or antifungal medications, and might recommend regular ear cleaning and flushing to help prevent future flareups. Among the substances your vet might suggest is tea tree oil, which contains properties that reduce swelling, disinfect the ear and kill harmful bacteria. Applying straight tea tree oil to your dog's ear can result in an allergic reaction, though, so dilution is necessary.
Tea Tree Ear Wash
Ask your vet for a recommended dilution of tea tree oil for use as an ear wash preventive for issues affecting your pet. You can concoct a homemade tea tree oil ear wash, as long as you have your vet's approval, by mixing equal parts deionized water, witch hazel and tea tree oil. Tea tree oil is toxic when ingested, so don't use it on parts your dog your dog he can reach with his tongue.