Chlorhexidine

What is chlorhexidine?

Chlorhexidine is a chemical active ingredient that belongs to the so-called biguanides. It was first synthesized in the 1950s and has been used in human and veterinary medicine ever since. Chlorhexidine has a strong antibacterial effect, which is achieved by destroying the cell membrane of microorganisms. It also inhibits the formation of dental plaque and reduces inflammation of the gums.

How is chlorhexidine used in dogs?

Chlorhexidine can be used in dogs in various ways, depending on the type of infection and how severe it is. The most common forms are:

• Solutions or sprays: These are used to clean and disinfect wounds, abscesses or rashes. They can be sprayed directly onto the affected area or applied with a cotton pad. The solutions or sprays should not get into the dog's eyes, ears or nose as they can cause irritation.
• Shampoos or rinses: These are used to treat skin infections such as pyoderma, dermatitis or malassezia. They usually contain a low concentration of chlorhexidine (0.5% to 4%) and other ingredients such as moisturizers or fragrances. The shampoos or conditioners should be lathered up after moistening the coat and massaged in thoroughly. After leaving on for around 10 minutes, they should be rinsed out with clear water.
• Gels or pastes: These are used to prevent or treat dental problems such as gingivitis, periodontitis or tartar. They usually contain a higher concentration of chlorhexidine (10% to 20%) and other ingredients such as fluoride or xylitol. The gels or pastes should be applied to the dog's teeth and gums once a day using a toothbrush or finger.
• Tablets or capsules: These are used to treat systemic infections such as urinary tract infections, respiratory infections or gastrointestinal infections. They usually contain a low dose of chlorhexidine (0.1% to 0.5%) and other active ingredients such as antibiotics or antifungals. The tablets or capsules should be administered with food or water.

What are the side effects of chlorhexidine in dogs?

Chlorhexidine is generally well tolerated and has few side effects in dogs. The most common are:

• Skin irritation: These can manifest as redness, itching, scaling or hair loss. They usually occur in sensitive dogs or in the event of an overdose. To avoid them, the correct concentration and duration of use of chlorhexidine should be observed. The dog's coat should also be dried well after use.
• Gastrointestinal complaints: These can manifest as nausea, vomiting, diarrhea or loss of appetite. They usually occur when chlorhexidine is taken orally. To avoid them, the correct dose and frequency of chlorhexidine should be observed. The dog should also have sufficient water available.
• Allergic reactions: These can manifest as swelling, respiratory distress, shock or anaphylaxis. They occur very rarely in the case of hypersensitivity to chlorhexidine. To avoid them, a skin test should be carried out before using chlorhexidine. In addition, the dog should be presented to a vet immediately if there are signs of an allergic reaction.