Antiseptics Safe and Toxic to Cats

What are antiseptics?

Antiseptics are antimicrobial substances that are applied to the skin or living tissue to kill or inhibit the growth of pathogenic organisms and prevent infection. They fall into two classes; germicides or bactericidal.

  • Germicides destroy pathogenic organisms (bacteria, viruses, fungi, protozoa etc.)
  • Bacteriocide destroys bacteria


  • Chlorhexidine
  • Iodine

Do not use

  • Alcohol
  • Phenols
  • Hydrogen peroxide
  • Essential oils
  • Quaternary ammonium
  • Neosporin

Many well-meaning pet owners assume that anything safe to use on humans is safe to use on cats; however, cats lack the necessary liver enzymes to break down many products which are safe to use in humans. Cats are also at an increased risk of toxicity due to ingesting anything which comes into contact with their coat when they groom.


Antiseptics safe to use on cats include chlorhexidine or iodine as the active ingredient. The chart below lists antiseptic products and their brand names which are safe for cats along with the dilution rate.



Chlorhexidine (Chlorhexiderm otic flush, Hexoral rinse, VetOne, Novalsan Solution, Novalsan Scrub, Microshield) Comes in 1% or 2% strength. Dilute 2% at a ratio of 2 tablespoons per 1 gallon of water. Do not use chlorhexidine inside the ears unless directed by a veterinarian as it is ototoxic.
Iodine (Betadine) Dilute to the colour of weak tea.


Avoid contact with the eyes when using antiseptics; these are for external use only.

Do not use

Antiseptics come in several groups, do not use any antiseptics in these categories:


Alcohol Either methyl or isopropyl. Brands include Isocol.
Phenols Substances that turn white in water. Brands include Dettol and TCP.
Peroxigen The most common type of peroxigen antiseptic is hydrogen peroxide.
Quaternary ammonium Brands include Savlon.
Essential oils Many of which, including tea tree and lavender are toxic to cats.
Neosporin Contains Polymyxin B, which has been known to cause anaphylaxis in cats.

Why are these antiseptics dangerous to cats?

  • Toxicity by ingestion of an antiseptic on the coat.
  • Ulcers and burns on the tongue when licking antiseptics.
  • Damage to the tissue.
  • Embolism (hydrogen peroxide).
  • Anaphylactic shock (Neosporin).

Peroxigen (hydrogen peroxide)

Causes: Damage to tissues and embolism

Hydrogen peroxide is made up of two hydrogen atoms and two oxygen atoms (H2O2). When it comes into contact with an open wound, it is known to produce bubbles, which occurs because blood and other living cells contain an enzyme called catalase, when hydrogen peroxide comes into contact with catalase it converts hydrogen peroxide into water (H2O) and oxygen gas (O) producing the characteristic bubbles. Not only are bacteria damaged during this process but healthy tissue.

When applied to deep cuts, hydrogen peroxide can cause a gas embolism (blockage of a blood vessel due to gas bubbles) when the oxygen produced by the decomposition of hydrogen peroxide enters a nearby blood vessel.

Essential oils

Causes: Toxicity and skin irritation

Essential oils are concentrated compounds obtained from plants. Many of these are highly toxic to cats if inhaled, applied to the skin, or ingested.

Tea tree oil

Causes: Damage to tissues and toxicity

Also known as melaleuca, tea tree oil is a popular antiseptic with antibacterial and antifungal properties. There are several toxic components in tea tree oil, including linalool, ocimene, alpha-terpinene, 1,8-cineole, terpinolene, camphene. 1,8 cineole is reported to be the major contributor to adverse reactions.

Some reports say that it is safe at a dilution of 0.1 to 1%, but can only be used on parts of the cat he is unable to lick. Even then, I wouldn’t risk it when there are safer alternatives.


Causes: Damage to tissues and toxicity

These coal-tar derivatives are common in antiseptics, disinfectants, and household cleaners. They turn white when water is added. Everyday products include Dettol, TCP, Lysol, and Pine-o-Clean. Phenols are incredibly toxic to cats, who are less efficient at excreting these chemicals.

These products are corrosive to the skin and mucous membranes, resulting in cell necrosis. Accumulation of phenols in the body, through the skin or via the skin, causes liver and kidney damage.


Causes: Damage to tissues

The application can cause burning and inflammation, and damage to the cells can slow down the healing process.

Quaternary ammonium

Causes: Chemical burns and ulceration
Quaternary ammoniums cause chemical burns and esophageal ulceration if ingested.


Causes: Potentially toxic/anaphylactic

Neosporin contains neomycin, polymyxin B, and bacitracin. It is not labelled for use on cats. Anaphylaxis has occurred in some cats who have received treatments containing polymyxin B.

How to treat a wound on a cat

What you will need

  • Sterile gauze or sanitary towel (to stop bleeding) and to clean the wound
  • Syringe (without needle)
  • Antiseptic
  • Salt
  • Water
  • Scissors
  • Soap and water

Saline solution

  • 1 cup (250 ml) water
  • .5 (half) teaspoon salt
  • Mix well


  1. Thoroughly wash hands with soap and water and dry.
  2. If the wound is bleeding, use clean gauze or a sanitary towel and apply gentle pressure to the injury. It can take up to 10 minutes for bleeding to stop.
  3. Flush (irrigate) the wound using a syringe filled with saline solution to remove debris. If you don’t have a syringe, use clean gauze or a soft cloth. Always flush or wipe debris towards the outside of the wound.
  4. Once bleeding has stopped, and the wound has been flushed, apply the antiseptic solution to a clean gauze strip, squeeze to remove excess liquid, and clean the wound. I recommend a solution over ointments and creams, which are easier to lick off and ingest.
  5. Continue to clean a 1-inch margin around the wound.
  6. Gently pat the wound and surrounding area with clean gauze.

When to see a veterinarian

  • Puncture wounds or long, deep wounds
  • Wounds that are longer than 1 inch (2.5 cm) or with jagged edges
  • Heavy bleeding
  • Burns
  • Animal bites
  • Wounds caused by an animal bite
  • If redness, discharge, or inflammation develop
  • Fever
  • Pain
  • Any minor wounds which aren’t showing signs of healing within 24 hours

Feature image Anton Gvozdikov, Shutterstock


  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio

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