5 Harmful Ingredients in Dog Shampoos to Avoid [Must Read]

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Various ingredients makeup pet shampoos and contribute to its performance in how well it cleans and it’s ability to lather.

Other raw materials like colour and perfume and additives are packaged into a shampoo. These additives drive the marketing value and of these shampoos.

Pet shampoos claim to spot-fix dry skin, dandruff and pesky flea problems.

What are dog shampoos?

Dog shampoos are different from the shampoos we use in the way they’re made. Dog’s skin is known to be more sensitive than human skin.

Their shampoos are meant to preserve healthy oils on the coat and skin. Their job is also to match the pH level of a dog’s skin that is neutral in the range of 6 to 7.

Dogs don’t sweat which makes their skin trap more dirt and toxins. Shampoo, for this reason, should be entrusted to thoroughly clean without stripping the skin off its natural properties.

Their shampoos are also custom made to suit different conditions, characteristics and breeds.

5 Dog Shampoo Ingredients to Avoid!

What contributes to a pet shampoo’s performance and shelf life is a concoction of compounds and chemicals. Some of these ingredients could prove harmful to both pet and human.

Sometimes products of thicker textures leave residues on a dog’s coat that can contain harmful chemicals. The resultant adverse effects from these chemicals are felt by both the pet and human caregiver.

Keep in mind 5 ingredients that can protect a pet from allergic reactions and other complications.


Stabilizers and preservatives are used in pet shampoos to prolong the life of these products without going rancid.

Formaldehyde is one a type of preservative that has been structured to enable a release of tiny amounts due to its toxic nature.

Studies have proven that constant use of products with Formaldehyde causes severe eye irritation, conjunctivitis and overall discomfort.

It is also known to lower immune response causing skin allergies, itching and blisters. It can easily be trapped in the respiratory tract of dogs, causing a decrease in respiratory rate and subsequent reactions.

Formaldehyde mostly hides at the end of a list of ingredients and could be masked by many names such as Bromopol, Doazolidinyl urea, DHDH hydantoin, Methylaldehyde Quaternium-7, -15, -31, -61, Oxomethane Formalin, Phenol Formaldehyde and Oxymethyline

Parabens are another class of preservatives and an ingredient to be avoided. They’re known to cause skin allergies and mimics the role of estrogen.

Parabens can be spotted as methyl, ethyl, propyl and butyl parabens. Methylchloroisothiazolinone and Methylisothiazolinone (MCI/MI) an alternative to parabens is a preservative that causes severe allergic reactions.


Chemicals that bind artificial fragrances to pet shampoo are potentially toxic and cause a number of health hazards. These chemicals are known as phthalates that are notorious in creating havoc with the endocrine system.

Canine skin being very sensitive is horribly affected in the presence of these chemicals. They’re known to cause harmful effects from skin reactions to neurotoxicity.

Typically, a shampoo could list the vague tag ‘fragrance’, which indicates the presence of phthaletes and not fragrance from plants or essential oils.


Surfactants are compounds that contain oil-soluble and water-soluble components. It acts as a soap, detergent, wetting agent, emulsifier, foaming agent, disinfectant etc.

Surfactants are known by a number of different terms and have harmful effects. Shampoos are made with hundreds of varieties of sulfates, which are a class of surfactants.

Sodium Lauryl Sulfate is a type of surfactant that is more than just a nuisance to a pet’s skin and eyes. It is a pesticide known to cause environmental damage.

SLS has a tiny molecular structure that passes through cell boundaries and eases the absorption of other chemicals, which can lead to organ damage.

Cocamide DEA (or cocamide diethanolamine) is a surfactant made from coconut fatty acids and acts as a detergent, foam stabilizer and an emulsifier.

Triethanolamine Cocamide-MEA and Cocamide DEA are toxic surfactants and classified as cancer causing ingredients.

Cocamidopropyl betaine contributes to a shampoo’s viscosity and foam. It is a chemical derivative of coconut oil but is known to cause skin allergies.

Other forms of sulfates to watch out for are Ammonium Lauryl Sulfate, Ammonium Laureth Sulfate, Sodium Coco Sulfate etc

Sulfates are not just skin and eye irritants but could also dull and damage the coat of a dog through repeated use.

Polysorbates are surfactants and a part of the fragrance, emulsifying and preservative ingredients. Sorbitol or sugar-alcohol turns into ‘Polysorbate-20’ when treated with 20 parts of ethylene oxide.

Surprisingly, ethylene oxide has a sweet scent on the surface of its harmful effects of being carcinogenic, mutagenic and irritating to the skin and eyes.

Further, products that contain ethylene oxide can easily penetrate into skin cells and turn carcinogenic.


Solvents like Isopropyl Alcohol and SD Alcohol 40 are used as cleaning agents and for dissolving oils. These solvents turn into acetone when they enter the body and increase the skin’s receptivity to other chemicals.

On the skin, it causes reactions through an imbalance of oils and moisture. It’s more toxic effects are felt in the nerves, lungs and heart.


Colors are an attractive marketing gimmick in pet and human shampoos. Without a dearth of natural pigments, chemical dyes are cheaper, making them a viable option to shampoo makers.

These colors are an artificial synthesis of petroleum and are linked to being carcinogenic and causes of birth defects.

Studies find it hard to point out the ill effects of artificial colors in shampoos due to the existence of other potentially harmful chemicals. Their toxicity however, must not be underestimated.


Dog Shampoos are not regulated to explicitly list ingredients by their chemical names. Unfortunately, the FDA does not require a revelation of contents from pet shampoo producers.

However, with safer alternatives in organic shampoos, these toxic options can be opted out. Labels like ‘organic’ and ‘natural’ should be supported by a disclosure of ingredients by a trustworthy organic shampoo.

Ultimately, it’s important to invest in a pet shampoo gently cleans without stripping the coat of its natural oils and qualities; one that is pH balanced, made with natural ingredients and smells good.

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