Hypochlorous Acid (HOCl) Topical

What is hypochlorous acid topical?

Hypochlorous acid (HOCl) topical (Aquacyn™, MicrocynVS®, Vetericyn Plus®, Vetericyn Plus VF®) is used for the management of skin conditions such as wounds, abscesses, abrasions, skin irritations, ulcers, post-surgical incision sites, and burns. It may be used to prevent or treat bacterial skin infections, including methicillin-resistant staphylococcus aureus (MRSA). Hypochlorous acid also has antifungal and antiviral properties and is reported to reduce inflammation, pain, and itching.

Hypochlorous acid topical products are labelled for use in all animals. They are available as over-the-counter medications or veterinary prescription medications, depending on the concentration of hypochlorous acid. 

How is hypochlorous acid topical given?

Hypochlorous acid topical comes in varying formats for topical use. Follow your veterinarian’s instructions for use.

• Liquid solution and spray are used topically on the skin.
• Liquid gel is used topically on the skin.
• Liquid ear cleanser is used topically, within the ear canal and outer ear.
• Liquid eye wash is used in and around the eye. 
• Clip hair around affected skin if required.
• Take precautions to avoid bleaching/staining carpets and furniture, clothing and jewelry.
• There are no known major precautions for humans exposed to hypochlorous acid topical, unless a known allergy to this drug exists

This medication should take effect within 1-2 hours and improvement in clinical signs should follow. 

What if I miss giving my pet the medication?

If you miss an application, give it as soon as you remember. However, if it is almost time for the next scheduled application, skip the missed dose and resume the regular schedule. Do not double up on applications to make up for a missed one.

Are there any potential side effects?

• Hypochlorous acid topical is not known to have any side effects. Products containing hypochlorous acid are generally non-toxic and safe if ingested or licked.
• The treated area may become red after this medication is applied due to an increase in blood flow. 
• 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.  

Are there any risk factors for this medication?

Hypochlorous acid topical should NOT BE USED in patients who:

• have corneal ulceration (if the product is intended for use in the eyes)
• have a ruptured tympanic membrane (if the product is intended for use in the ears)

Although no allergic reactions have been reported, 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 and notify your veterinarian if you have any concerns. 

Are there any drug interactions I should be aware of?

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

Is any monitoring needed with this medication?

At home, monitor for any side effects such as those noted above. If any side effects occur, discontinue the medication and contact your veterinarian. Follow your veterinarian’s recommendations regarding:

• when your pet needs to be rechecked
• what tests may need to be performed before and during treatment with this drug

Your veterinarian will let you know when they want to reassess your pet to ensure the medication is working and not causing side effects. 

How do I store hypochlorous acid topical?

• Store at controlled room temperature.
• If frozen, thaw and shake contents before use.

Ask your veterinarian for specific disposal instructions. Do not flush medicines down the sink or toilet unless instructed to do so.

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. 
• Adverse effects should also be reported to the FDA or Health Canada.