Puppies get into messes. Potty training comes with stinky risks, and curious puppies get into all sorts of odorous situations. Veterinarian Cheryl Yuill says that if a puppy soils itself, “there is no question that it should be bathed immediately.” If you find that your puppy requires frequent baths, however, she recommends talking to your veterinarian about the best pet shampoo for your dog’s age, breed and skin type.

Adult and senior dogs should be bathed when necessary, but not more than that. In other words, only wash your dog if he is dirty or starts to get that distinctive doggy odor. Terese DeManuelle, a veterinary dermatologist, says, “it’s safe to bathe your dog with veterinary shampoo once a week.” However, there is such a thing as too much cleanliness.

Overbathing, especially with human shampoos or detergents, strips the beneficial oils from your dog’s fur and can cause irritation. The pH in human shampoos, even baby shampoo, is not designed for dogs. This is why Yuill strongly recommends using a shampoo recommended by your veterinarian or a shampoo approved for use on dogs. Some breeds require more baths than others. Dogs with oily coats, like water breeds and hounds, may require more frequent baths to keep them smelling fresh and clean and their coats healthy. Labrador retrievers, basset hounds and beagles are especially prone to greasy coats, so if you own one of these breeds, be prepared to share your shower on a fairly regular basis.