Cat Shampoo ingredients to avoid

Not Sure What Cat Shampoo Ingredients to Avoid?

Cats are highly reactive to certain chemicals and natural compounds that are not safe for them, yet are often used in pet shampoos. This is why it’s important to know what cat shampoo ingredients to avoid. Here you will find a list and description of those ingredients to make finding a safe shampoo easier.

  • Pyrethroids
  • Phenol
  • Sulfates
  • Parabens
  • Artificial
  • Fragrances
  • Formaldehyde
  • Mineral oil
  • Propylene
  • Glycol
  • Methylchloroisothiazolinone
  • Pennyroyal
  • Wintergreen
  • Oil of sweet birch
  • Pine oils
  • Ylang Ylang oil
  • Peppermint oil
  • Cinnamon oil
  • Pennyroyal oil
  • Clove oil
  • Eucalyptus oil
  • Tea Tree oil

Cat Shampoo Ingredients to Avoid Differ from Dogs

There are myriad cat shampoos on the market that make for great cleansers, however, there also are those that contain cat shampoo ingredients to avoid. Some are highly toxic and others simply just are not healthy for a cat’s skin and fur. An article written by The Humane Society of the United States suggests that:

“When bathing pets, use only shampoos formulated for the particular species and follow the directions. Do not assume shampoos for dogs are appropriate for cats, unless the label specifies both species.”

Many dog shampoos contain ingredients that are toxic to cats. Using them can cause harm, particularly if ingested when self-grooming. Some health concerns that arise from such situations are diarrhea, vomiting, and nausea, all of which can lead to dehydration, which in turn, could be fatal, Cats lack specific liver enzymes that cannot break down toxins as easily as dogs. Their small bodies don’t handle toxins well. This is why it important to know what cat shampoo ingredients to avoid.

Natural Substances Used in Cat Shampoos that Should be Avoided


The Chrysanthemum Family of Toxic Insecticides


Potentially Toxic in Flea

& Tick Cat Shampoos

Pyrethroids refer to a group of substances that include phenothrin, etofenprox permethrin, and pyrethrins. Pyrethroids are commonly used in killing fleas. The International Cat Care Organization details why Permethrin is dangerous.

“Permethrin is a synthetic pyrethrin. Pyrethrins are naturally occurring insecticides extracted from the flowers of Chrysanthemum cineraria folium. Permethrin is used in some flea spot-on products made for dogs, and occasionally (in lower doses) in flea powders and collars for cats. Unfortunately, exposure to concentrated may result in serious illness and even death in cats”

The use of pyrethroids in shampoos increases the likelihood of toxicity in mammals that are exposed. Their toxicity is not specific to any one species so while it will kill fleas and other insects, it could also prove to be dangerous to cats.

Although not recommended, dogs may be exposed to permethrin in products that are applied to their skin for flea and tick treatments. The National Pesticide Information Center writes “Permethrin is more toxic to insects than it is to people and dogs. This is because insects can’t break it down as quickly as people and dogs. Cats are more sensitive to permethrin than dogs or people because it takes their bodies a long time to break it down.”

Chemical-Based Cat Shampoo Ingredients to Avoid


Phenol is found in shampoos that contain 3% hexachlorophene, coal tar shampoos, and keratolytic shampoos. Once it is used on a cat or kitten, phenol is absorbed quickly in the intestinal tract and could potentially cause liver or kidney damage within 12-24 hours.

Not only is phenol unsafe as a shampoo, but also can be risky when cats are exposed to it even as a cleaning agent. Phenol is defined as a mildly acidic toxic white crystalline solid obtained from coal tar and used in chemical manufacture, and in dilute form (under the name carbolic ) as a disinfectant.

Danielle Bays, senior analyst for cat protection and policy for the Humane Society of the United States has this to say about the use of phenol: “Both cats and dogs are at risk, but cats are particularly vulnerable because they are small, their bodies do not handle toxins as well, as they lack certain liver enzymes and they are constantly licking their fur, says.”

According to the Canadian Veterinary Medical Association, “Cats’ livers are deficient in a process called “gluconuridation,” an important step in the metabolism of many compounds. As such, chemicals that are metabolized by other species often accumulate or are broken down into toxic metabolites in cats. This is especially true for compounds called “phenols” which contain an “aromatic” or “benzene” ring.”


Suds Do Not Equate to Healthy Cleaning

The two most widely used sulfates are sodium lauryl sulfate (SLS) and sodium laureate sulfate (SLES). They are both inexpensive foaming agents that can be effective in removing dirt and oil from the coat. Unfortunately, they can impact the protective layers of the skin and hair, causing excessive dryness. It’s important not to equate suds to cleansing effectiveness, as there are many substances that remove dirt and oil that are healthy for a cat’s skin. In fact, in most cases, the less suds, the better. Furthermore, sulfates are often tested on animals to measure the level of irritation to people’s skin, lungs and eyes. We can only assume the testing is painful to these animals.


Increasing Shelf Life at the Expense of Animals & Earth?

Parabens are used as preservatives in pet shampoos and other grooming products as they increase the shelf life. Parabens are bad for the environment. However, they are cheap and readily available so manufacturers continue to use them in cat shampoos. The most common parabens are methylparaben, propylparaben, butylparaben and ethyl paraben. Unfortunately, parabens penetrate cats’ skin. They are linked to certain cancers and may cause reproductive issues and tumor growth.

Beware of using shampoos scented with artificial fragrances

Artificial Fragrances

Don’t Be Mislead by the Lovely Scent. It’s One of The Main Cat Shampoo Ingredients to Avoid

Artificial fragrances are used to disguise hundreds of harmful toxic chemicals in cat shampoos. If a cat shampoo label includes an artificial fragrance, avoid it. Artificial fragrances are used because they cost less than natural plant extracts and essential oils. But one of the main dangers in using artificial fragrances is many are made of petrochemicals from crude oil, which is a highly toxic substance. 

Also, cat shampoos often include phthalates, one of the most used artificial fragrances. It is known for disrupting the hormonal balance. Unfortunately, many of these artificial fragrances contain chemical structures akin to pesticides. They may potentially slowly poison a cat. 


Don’t Use. Don’t Inhale.

Formaldehyde releasers are an extremely common preservative in cat shampoos. Formaldehyde is known as carcinogenic to humans that have been found to initiate and promote the formation of tumors. When formaldehyde is present in cat shampoos, it is equally harmful to their humans. They too will be exposed by inhaling the formaldehyde that is off-gassed from the product, by ingesting, it or absorbing it through the skin. Furthermore, this dangerous preservative found in cat shampoos is tested on animals. PawPurity suggests avoiding cat shampoos that use formaldehyde releasers.

Mineral Oil 

Disruptive to Cat Skin Natural Oils

While mineral oil in cat shampoo may help the skin retain moisture, it also is a protective barrier that prevents the skin from releasing its natural oils and eliminating toxins. Simply put, it is a liquid mixture of hydrocarbons from crude oil. Mineral oil a possible toxin and may cause allergies. There are articles online suggesting that pet owners put a drop of mineral oil in their cat’s eyes before a bath, so the mineral oil can protect the eyes from stinging if the shampoo gets into them. Do not do this.

Propylene Glycol

Another of the Chemically Engineered Cat Shampoo Ingredients to Avoid

Propylene Glycol is a skin solvent, conditioner, and humectant. This ingredient is used in cat shampoos as a penetration enhancer. It’s also a suspected immune system toxin, neurotoxin, and skin and reproductive toxin.


Know What Manufacturers are Using as Preservatives in Cat Shampoos

Methylchloroisothiazolinone is a preservative used in pet shampoos. It’s an antifungal, however, it also is a carcinogen associated with organ failure. This is another of the potentially toxic ingredients that continue to be used in pet shampoos even though it has been banned in Japan and Canada.


Highly Toxic to Cats

Pennyroyal Plant – Highly Toxic to Cats

Pennyroyal is a known toxin to cats and should be avoided. Pennyroyal has been known as an insect repellent for centuries. It was once used to control fleas on pets, but no longer. However, pet owners that use shampoos containing pennyroyal to treat or prevent flea infestations that could be putting their cats in danger. Exposure a cat’s skin to pennyroyal may be toxic, causing hepatic necrosis or liver failure. Should this happen, aggressive veterinary care is needed to try to support the liver and prevent liver failure. To find out about natural flea prevention treatments, read this article about the safety of flea prevention treatments for cats and dogs. According to the Pet Poison Helpline,

“Pennyroyal is oil from Mentha Pulegium. It is commonly known as European Pennyroyal or squaw mint. Pennyroyal has a long history in folk medicine with its use as an insect repellent. It can be used by unsuspecting pet owners to treat flea infestations or to try to prevent flea infestations. Again, oral or dermal exposures can both result in toxicity.”

Essential Oils – Natural Cat Shampoo Ingredients to Avoid

While essential oils in cat shampoos are coming into vogue, some should be avoided.

  • Tea tree
  • Lavender
  • Wintergreen 
  • Sweet birch
  • Pine
  • Ylang Ylang
  • Peppermint 
  • Cinnamon
  • Pennyroyal
  • Clove 
  • Eucalyptus 

The ASPCA points out that lavender oil is not safe for cats and can cause nausea and vomiting. However, the most often essential oil you will see in cat shampoos is tea tree oil and it’s one of the most toxic when not sufficiently diluted. Its true name is Melaleuca Oil. Too often, well-meaning pet owners use shampoo or treat skin conditions or external parasites such as fleas using this essential oil. It is easily absorbed through the skin. In concentrated form, tea tree oil may cause depression, ataxia (uncoordinated gait), rear leg paralysis, vomiting, hypothermia, and skin irritation. The signs of intoxication can be present for up to four days with a veterinarian’s aggressive care and treatment.

The Pet Poison Helpline understands the dangers of tea tree oil.

“Tea Tree Oil is known for its antifungal and antibacterial properties, and possibly for its antipruritic, anti-inflammatory, and anti-parasitic effects. Tea tree oil is often found in varying concentrations and high concentrations should never be used on pets. As little as 7 drops of 100% oil have resulted in severe poisoning, and applications of 10-20 ml of 100% oil have resulted in poisoning and death in both dogs and cats.”

Making a list of toxic versus non-toxic essential oils depends on the process used, the pureness of the product, supplier quality of the ingredients, dilution factors, the amount of exposure, and the other compounds that are used in preparing a specific brand of oil.

“According to the CVMA, tea tree oil and lavender are two essential oils to avoid. Cats can also develop watery, irritated eyes and noses from chemical irritation of the respiratory or eye lining membranes or develop dermatitis from direct skin contact. In people, essential oils are increasingly understood to produce positive patch tests for hypersensitivity—lavender and tea tree oil are the most cited examples.

Essential oils have many benefits with only a handful being toxic. While PawPurity products are solely natural and use essential oils for specific benefits for use in cat shampoos and other products, it is a priority to meet the criteria that ensure they are safe.

The A-List

This A-List of cat shampoo ingredients to avoid is designed to help cat owners make good choices in the products used on their cat’s skin and fur. PawPurity urges cat owners to read labels to ensure that what they are putting on their animals are safe. Prevention is key to keeping cats happy and healthy. And as more products come onto the market, PawPurity’s goal is to keep cat lovers updated on the safety and effectiveness of the ingredients used. If you are interested in a solution, see our all-Natural Flea & Tick Shampoo for both Cats & Dogs, our Intensive Nourishing Shampoo with Calendula, Aloe & ACV or Contact us with any further comments or questions about our recommendations.