A flea infestation can catch you off-guard. When your pet is covered in fleas and itching like crazy, you’ll do anything to help them find relief. Ready to throw the kitchen sink at the problem, you might find yourself reaching for the dish soap. After all, you may have seen it used on commercials to clean baby ducks. But is using dish detergent it really the best way to get rid of fleas on your pet?

How Dish Detergent Kills Fleas
Fleas have a protective covering called a cuticle, or exoskeleton, with a waxy, waterproof layer. This layer keeps moisture from getting in or out of the flea. When it falls into a body of water, a flea can survive for up to a week without drowning. So, simply washing your pet with water will not kill fleas.
Dish detergent contains potent chemical surfactants that break down grease on dishes so it can wash down the drain. These surfactants also break down the flea’s cuticle, allowing water to enter their body, and also disrupt the surface tension on the water so they sink, essentially drowning them.

How Dish Detergent Affects Your Pet’s Skin
The problem lies in how chemical surfactants affect your pet’s skin. In order for it to work, the lather has to sit on your pet’s coat for about five to ten minutes. In that time, it will not only compromise the flea’s protective layer, but your pet’s skin as well.
Dogs, cats, humans, and other mammals have a protective layer of their own, called the epidermis. The epidermis is normally covered by a layer of sebum, or natural oils that keep the skin from drying out. Harsh detergents strip the skin’s natural oils, leaving it dry and itchy.
The surface of your pet’s skin has a neutral pH - not too basic, not too acidic. This environment allows beneficial bacteria to thrive while limiting the growth of harmful pathogens. Dish soap has a high or basic pH and can throw off the skin’s natural balance.
One bath with dish detergent is unlikely to cause a healthy pet serious harm. However, if their skin is sensitive, or if their skin is irritated due to flea bites, removing the protective sebum can leave them vulnerable to infection.

Can Any Soap or Shampoo Kill Fleas?
All soaps and shampoos contain surfactants that help remove dirt and residue from hair, skin, and fur. Your pet’s normal shampoo can kill fleas without throwing off the skin’s pH balance or stripping its oils. However, the more mild formulation will take longer to work. You will need to lather up your pet and allow the shampoo to sit for ten minutes or more until the fleas die off.

Keeping Your Pet Flea-Free
Using a flea and tick preventative is the best line of defense against flea infestations. Preventatives contain ingredients that continuously kill fleas. So even if a flea lands on your pet, it’s unlikely to survive long enough to reproduce and cause a full-blown infestation.
It’s also a good idea to keep flea shampoo on-hand for emergencies. Flea shampoos contain ingredients that not only kill fleas on contact, but also repel them for up to a week after application. Best of all, it leaves your pet’s skin healthy and hydrated. Remember, dish soap is for dishes, and flea shampoo is for fleas!