Acetic Acid + Boric Acid Topical

By Lauren R. Forsythe, PharmD, MBA, DICVP; Kayla Hyland, DVM

What is acetic acid + boric acid topical?

Acetic acid + boric acid topical (brand name Malacetic®) is an antibacterial and antifungal medication used in dogs and cats to treat surface skin infections caused by bacteria or yeast. Some formulations may be used to treat ear infections in dogs and cats. It may be used in other species.

This medication may be part of a combination product that includes other medications, such as ketoconazole, chlorhexidine, or a steroid. Acetic acid + boric acid topical is available over the counter (OTC) but should only be used under the direction of a veterinarian.

The U.S. Food and Drug Administration (FDA) does not review veterinary health products (e.g., shampoos, cleansers, topical products) for safety or effectiveness before they are sold to the public. Manufacturers of veterinary health products must ensure their products are safe and labeled accurately.

The FDA requires that these products contain a disclaimer that says, “This product is not intended to diagnose, treat, cure or prevent any disease.” Health Canada licenses “veterinary health products” after reviewing safety, efficacy, and manufacturing information provided by the manufacturer. These products are not tested by Health Canada.

Your veterinarian is the best source of information about the safety of veterinary health products in pets. These products can also have side effects, like pharmaceuticals. Although the information in this handout may be helpful, it also may be incomplete and may not represent the full range of effects this product could have on your pet. Follow your veterinarian’s directions and cautions carefully and report any concerns to them.

How do I give my pet acetic acid + boric acid topical?

  • Acetic acid + boric acid topical comes in shampoo, liquid, or wipe form.
  • Shampoos, liquids (sprays or droppers), and wipes are applied topically (directly onto the skin).
  • Follow your veterinarian’s directions for the specific product prescribed for your pet.
  • Do not let any animal lick or chew affected sites for at least 30 minutes after application.
  • Give this medication to your pet for the entire time prescribed by your veterinarian, even if it appears your pet is feeling better.
 

This medication should take effect within 1 to 2 hours and improvement in clinical signs should follow, depending on the severity of clinical signs.

What if I miss giving my pet the medication?

If you miss a dose, give it as soon as you remember, and then continue with the regular dosing schedule. However, if it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not give the pet two doses at once or give extra doses.

Are there any potential side effects?

Acetic acid + boric acid topical may cause the following side effects:

  • Irritation or reddening of skin at application site
 

Serious adverse reactions may occur. If any of the following signs develop, stop giving acetic acid + boric acid topical and contact your veterinarian immediately:

  • An allergic reaction such as irregular breathing, rash, fever, puffiness and swelling around the face
 

Drug sensitivities can develop over time with repeated exposure. Your pet may have no reaction after the first few doses but may develop a sensitivity later. It is important to watch for signs of an allergic reaction over the entire course of treatment. Other side effects may occur. If you notice anything unusual, contact your veterinarian immediately.

Are there any risk factors for this medication?

DO NOT USE acetic acid + boric acid topical in:

  • Pets that are allergic to any component
 

USE WITH CAUTION in:

  • Pets that are using it long-term as part of a combination product containing a steroid (potential systemic effects can occur with long-term steroid use)
 

Are there any drug interactions I should be aware of?

There are no documented drug interactions for this medication. Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this medication?

  • Your veterinarian will let you know when and how they want to reassess your pet to ensure the medication is working and not causing side effects.
  • At home, monitor for any side effects such as those noted above. If any occur, stop using the medication and contact your veterinarian.
 

How do I store acetic acid + boric acid topical?

  • Store the medication in its original container at room temperature. Do not freeze.
  • Protect from light and moisture. 
  • Keep medication out of reach of children and pets.
 

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Be prepared to provide information about the product and your pet's weight and symptoms.

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