Everyone in the family, including your dog, appreciates the benefit of an effective flea preventive. However, dogs will be dogs, and sometimes an unplanned bath is necessary. If your pup got into something right after receiving his monthly flea preventive, you'll have to wait a bit before you bathe him. It could be as short as a couple of hours or as long as a day, depending on the treatment.
Topical Flea Preventives
There's a wide variety of flea preventives on the market for dogs. Since they use different ingredients, they offer different protection. Some kill adult fleas, others add flea larvae to the mix, while others kill ticks as well. Applying the medication to the dog's skin, ideally at the base of the skull, allows it to be absorbed into his skin, hair follicles or bloodstream to come in contact with the fleas. Usually the insecticides work by destroying the flea's nervous system. The rate at which the insecticide is absorbed into your dog's system determines how quickly you'll be able to bathe your dog after administering his monthly dose.
Wait a Day
If you're using Frontline Plus on your dog, you'll need to wait 24 hours before giving him a bath or allowing him to swim. The company's website notes the preventive will be effective for 30 days, even if the dog gets wet. Bio Spot also requires a 24-hour waiting period before bathing or swimming.
Wait Less Than a Day
Revolution, which kills fleas, flea eggs and their larvae, as well as other parasites, lasts 30 days. The company's website states the product will be completely effective if you bathe your dog two hours after applying the insecticide. A dog using Bayer's Advantage Multi can be bathed 90 minutes after applying the medication. Pet Armour Plus recommends waiting 12 hours after administration before you give your dog a bath.
Finally, Bath Time
Keep in mind that if you're using a flea collar or an oral flea preventive, it doesn't matter when you bathe your dog. The wait time for a topical depends on how long it takes for the product to begin to do its work so it won't be disrupted by water. If you're unsure about the wait time for your dog's flea treatment and you must bathe your dog, call your vet or contact the manufacturer. When it is time to give your pup his bath, remember to use a mild shampoo formulated for dogs so his skin won't be stripped of its essential oils.