Finding a louse on your dog means there could be 100 around!! Here is my practical experience, hoping it can help you! The insecticides sold at pet hospitals come in various forms, but most doctors will recommend moderately priced medicines, usually around 30 yuan, and the quantity is very small. Here, I suggest you use "Chu Lai Ling"; it is very cheap at 5–10 yuan/box. After dilution, give your dog a medicated bath, wash again after about 5 days, aiming to kill the eggs and newborn lice. Use sulfur soap as the detergent because sulfur soap can also kill fleas and lice. Note the details: 1. Soak the dog’s entire body thoroughly with the diluted solution, keep it on for some time, then apply sulfur soap, keep for a while again, then rinse to ensure the lice are poisoned to death. 2. Dry your dog immediately after the medicated bath and prevent the dog from licking its fur. 3. Try to wear as little clothing as possible when bathing your dog, because fleas can transfer onto human clothes. Give it a try!!