What’s in Your Dog’s Shampoo? Avoid These Ingredients

What’s in Your Dog’s Shampoo? Avoid These Ingredients

Have you ever looked at the ingredients in your pet’s shampoo? 

There are hundreds, if not thousands, of varieties of pet shampoo. Whatever your dog’s needs, you can find a sweeping array of products on the shelves of your local pet store and are abundant across the Internet. However, not all dog shampoos are created equal, and many contain ingredients that can irritate and harm your dog’s skin. When shopping for a pet shampoo, be sure to examine the ingredients listed on the bottle before making a purchase. 

Avoid Using People Shampoo on Your Pooch 

First and foremost, never use shampoos or conditioners that are made for humans on your dog. Our skin is much less sensitive than a dog’s, and human shampoos are designed to wash off the natural oils and wax on our hair. That’s fine for humans, but it will leave your dog’s coat dull and brittle and can cause skin irritation, inflammation, redness, itching, drying, and can even lead to skin infections with repeated use. 

When it’s time for Fido’s next bath, be sure to avoid the following dog shampoo ingredients or else you could negatively impact your pup’s health.


Parabens are a cheap and effective preservative widely used by the cosmetics industry to prolong product shelf life and to stop creams and shampoos from developing fungal growth. In view of the various scientific studies on parabens, many people are opting to use paraben-free products for themselves and their pets. In pet products, parabens are often present in dog shampoos. Parabens can cause skin irritation, rashes, and skin infections in dogs. Parabens also mimic estrogen, and a 1980s study on paraben sensitivity in dogs suggested that its usage on female pooches drives males wild and stimulates arousal when the females are not in heat. 

To avoid this nasty ingredient, check your pooch's beauty products for methyl, ethyl, propyl, and butyl parabens. 


If a scent comes from natural sources, chances are it will say so on the packaging. After all, it’s a good selling point. So, if you see “fragrance” listed under dog shampoo ingredients, it’s good to get suspicious. Fragrance can signify hundreds, or even thousands, of unnatural ingredients you don’t want to put on your dog. 


Ethanolamines are a group of chemicals made from proteins (amino acids) and alcohol that have ammonia-like odors. The three ethanolamines commonly found in your dog shampoo are monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA). Manufacturers use ethanolamines in the synthetic development of dog shampoos as they create a creamy texture with good foam. They also reduce the surface tension of substances so that water-soluble and oil-soluble ingredients can blend together, and they can help control the pH level of a product. Ethanolamines are so prevalent in pet shampoos, that customers often balk at shampoos that are made without them because they are less viscous. 

When ethanolamines are used in the same product as certain preservatives or other ingredients, they break down into nitrogen and can form what is called nitrosamines. The nitrosamines are classes of chemicals that are thought to be carcinogenic, have reproductive toxicity, developmental toxicity, and organ system toxicity.

The European Commission prohibits DEA in cosmetics to reduce contamination from carcinogenic nitrosamines. Some nitrosamines can be absorbed through the skin.

Unfortunately, there are a lot of different names for MEA, DEA, and TEA, so avoiding it isn’t as simple as checking for those three words on a label. 

What to look for (and avoid) on pet shampoo labels: 

  • Diethanolamine (DEA)
  • Cocamide DEA 
  • DEA-cetyl phosphate
  • DEA oleth-3 phosphate
  • Lauramide DEA
  • Myristamide DEA 
  • Oleamide DEA 
  • Monoethanolamine (MEA)
  • Cocamide MEA 
  • Linoleamide MEA 
  • Stearamide MEA
  • Triethanolamine (TEA)
  • TEA-lauryl sulfate

Artificial Colors 

    That hot pink dog shampoo might look neat, but it could contain potentially harmful and unnatural dyes. Artificial colors are synthesized from petroleum and are linked to organ damage, cancer, birth defects, and allergic reactions. Artificial colors aren’t “pure” chemicals. Many of them are contaminated with byproducts and are purchased by the manufacturer to visually enhance the product. It’s best to choose a pet shampoo that’s free from artificial colors or dyes. 


    Sulfates are a class of chemicals that manufacturers use as cleansing or foaming agents. Many household products, such as foaming cleansers, toothpaste, and pet shampoos, contain sulfates. Sulfates provide the sudsy texture that occurs when a person mixes a product, such as a pet shampoo, with water. Manufacturers will tell you they use sulfates (aka detergents) in dog shampoo because in addition to making the product sudsy, the fur sleek and shiny, they capture oil and dirt that washes out in the rinse. Sounds great, right? What they don’t tell you is while the sulfates are removing excess oil and dirt, they are also stripping the natural oils and irritating the skin, causing redness, drying, and itching, sometimes leading to skin infections. 

    In addition, some of the byproducts (or contaminates) of sulfates, such as 1,4-dioxane, sodium laureth sulfate (SLES), and ammonium laureth sulfate, are all known cancer-causing agents. California’s Proposition 65 list of chemicals known or suspected to cause cancer or birth defects includes 1,4-dioxane. The EPA has listed 1,4-dioxane as a likely human carcinogen, with the potential to cause nasal and liver tumors. Noncarcinogenic effects include effects on the nervous system, liver, and kidneys. 1,4-dioxane can also enter the natural environment through waste streams such as wastewater treatment plants, landfills, and manufacturer waste streams.

    If there are bubbles in your pet’s shampoo without shaking it, it likely has sulfates and should be avoided. 

    What to look for (and avoid) on pet shampoo labels:

    • Sodium Lauryl Sulfate (SLS)
    • Sodium Laureth Sulfate (SLES)
    • Ammonium Lauryl Sulfate (ALS)
    • Ammonium Laureth Sulfate (ALES)
    • Sodium Coco Sulfate (SCS)

    If you do use a shampoo with sulfates, you should be very careful around your pet’s eyes. SLS has been linked to the development of cataracts, and in young pets, SLS may even cause permanent damage to the protein formation in the eyes leading to blindness. Overall, it’s best to choose a sulfate-free shampoo for your pooch, and for yourself for that matter. 

    Methylchloroisothiazolinone (MCI)

    A good rule of thumb is to avoid dog shampoo ingredients that you can’t pronounce, and methylchloroisothiazolinone makes a perfect example of that. It may already be banned in Canada and Japan, but unfortunately it’s not extinct in the pet product industry just yet. Methylchloroisothiazolinone is added to shampoos as an anti-fungal and a preservative – but it’s a known carcinogen that’s associated with organ poisoning. Yikes! Best to avoid it. 

    The Better Shampoo for Your Dog: The Ecology Works Anti-Allergen Pet Shampoo 

    Our Anti-Allergen Shampoo has a plant and mineral-based formula that’ll leave your dog smelling and feeling amazing. Each carefully selected ingredient offers unique benefits. In fact, this shampoo eliminates allergens from pet dander, it helps to control fleas and ticks, conditions and softens your pet’s coat, keeps your pet smelling fresh longer, and so much more, all while being gentle on the skin and fur. It’s great to use on pets that have allergies and skin sensitivity. 

    Our formula is fragrance-free, dye-free, paraben-free, sulfate-free, and free from ethanolamines and methylchloroisothiazolinone (you’re still trying to pronounce it, aren’t you?!). It’s also 100% biodegradable, making it an environmentally-friendly choice. 

    Experience the difference offered by dog shampoo that was made with your dog’s well-being in mind. Your dog is sure to thank you! 

    At The Ecology Works, all of our products are made with the well-being of people, pets, and the planet in mind. Learn more about the science behind our products and how to make more eco-friendly choices. If you have any questions, please feel free to Contact Us or message us on Facebook. We’re here to help.