Medicated Shampoo for Horses: How to Bathe a Horse With Skin Issues

Quick answer

Use a medicated shampoo only after your veterinarian confirms a bacterial or fungal skin issue, then bathe in a safe, warm area with thorough wetting, 5–10 minutes of contact time, and complete rinsing. Repeat at the interval your vet recommends, and stop if the skin worsens.

Skin problems in horses are common, and a medicated shampoo is one of the most useful tools for treating them. But the shampoo only works if it stays on the skin long enough and gets rinsed off completely. This guide walks through a safe bathing routine for horses with skin issues, using BioHex Shampoo for Cats, Dogs, & Horses as a practical example.

Before you start, get a diagnosis. Many equine skin conditions look alike, and a product that helps one may irritate another. Your veterinarian can confirm whether the problem is bacterial, fungal, parasitic, or allergic, and whether a medicated shampoo is appropriate.

What a medicated shampoo does and does not do

Medicated shampoos for horses contain active ingredients such as chlorhexidine, miconazole, or copper naphthenate. These ingredients are chosen to reduce bacteria or fungi on the skin. BioHex Shampoo for Cats, Dogs, & Horses, for example, combines chlorhexidine, miconazole, and MicroSilver BG, and is described as a broad-spectrum, soap-free cleanser for skin conditions responsive to those ingredients.

A shampoo is not a cure on its own. It removes surface debris and reduces organisms, but it cannot fix underlying allergies, poor barn hygiene, or a horse that stays wet for hours. Think of bathing as one part of a plan that also includes drying, clean bedding, and treating any other horses or equipment that may be involved.

• Check the label for the active ingredients and the contact time your vet recommends.
• Do not use a human shampoo or a harsh detergent on broken or inflamed skin.

Set up a safe bathing area before you wet the horse

Choose a warm day or a wash rack with warm water. Cold water makes many horses tense and can make it harder to get a thorough lather. Have a hose with a spray nozzle, a bucket of diluted shampoo, and plenty of towels ready before you bring the horse in.

If the horse has a painful or open skin area, ask your vet whether bathing is safe or whether you should spot-treat instead. A horse that is difficult to handle in the wash rack may need a calm assistant or a different approach.

• Use a non-slip mat in the wash area.
• Keep the horse tied loosely so it can move its head if it becomes anxious.

Wet the coat thoroughly, then apply the shampoo

Wet the horse from the neck down, avoiding the eyes, ears, and muzzle. The coat must be saturated all the way to the skin, because shampoo that sits on top of the hair will not reach the organisms. Part the hair with your fingers to check that water is reaching the skin.

Dilute the shampoo according to the label or your vet's instructions, then work it into the coat with a sponge or your hands. For a product like BioHex, shake well before use. Focus on the areas with skin issues, but you can wash the whole body if your vet advises it.

• Do not pour shampoo directly into the eyes or ears.
• If the horse has a thick winter coat, you may need to work in smaller sections.

Let the shampoo sit for the full contact time

Contact time is the step most people rush. Medicated ingredients need time on the skin to work. Your vet or the label will specify how long to leave the shampoo on; common recommendations range from 5 to 10 minutes. Set a timer so you do not guess.

While the shampoo sits, keep the horse calm and prevent it from licking or rubbing the treated areas. If the horse starts to shiver, rinse immediately and move it to a warm, draft-free place.

• A timer on your phone is more reliable than counting in your head.
• Do not cover the horse with a blanket while the shampoo is on.

Rinse completely and dry the skin

Rinse with clean water until the runoff is clear and no suds remain. Shampoo residue can irritate skin and attract dirt, so this step matters as much as the washing. Check the armpits, groin, and under the mane, where soap tends to hide.

After rinsing, remove excess water with a sweat scraper and towels. Let the horse dry in a warm, clean area. If the weather is cold, use a cooler or blanket only after the skin is mostly dry, and change it if it becomes damp.

• Do not let the horse roll in mud immediately after bathing.
• Clean and dry any blankets or grooming tools that touched the affected areas.

Repeat at the right interval and watch for changes

Your vet will tell you how often to bathe. Some conditions need repeated baths every few days, while others need only one or two. More frequent bathing is not automatically better and can dry out the skin.

Take photos of the affected areas before each bath so you can compare. If the skin becomes more red, raw, or painful, or if the horse develops new lesions, stop and call your vet. Some skin infections need oral or topical medication in addition to shampoo.

• Keep a simple log of bath dates and what you used.
• Do not share towels or brushes between horses with active skin issues.

Step-by-step bathing routine

1. Get a diagnosis first: Have your veterinarian examine the skin before you buy or use any medicated shampoo. Many equine skin conditions look similar, and the wrong product can delay healing. Checkpoint: you know whether the issue is bacterial, fungal, parasitic, or allergic.
2. Set up a warm, safe wash area: Use warm water, a non-slip surface, and keep the horse loosely tied. Have towels, a sweat scraper, and your diluted shampoo within reach. Checkpoint: the horse is calm and the area is ready before you wet the coat.
3. Wet the coat to the skin: Soak the horse from the neck down, avoiding eyes, ears, and muzzle. Part the hair to confirm water reaches the skin. Checkpoint: the coat is saturated, not just damp on top.
4. Apply and lather the medicated shampoo: Shake the bottle well, dilute as directed, and work the shampoo into the coat with a sponge or hands. Focus on affected areas. Checkpoint: you have a visible lather on the areas that need treatment.
5. Let it sit for the full contact time: Set a timer for the contact time your vet or the label recommends, usually 5 to 10 minutes. Keep the horse calm and watch for shivering. Checkpoint: the shampoo stayed on the skin for the full time, not just a quick rinse.
6. Rinse until the water runs clear: Rinse thoroughly, checking the armpits, groin, and under the mane. Remove excess water with a scraper and towels. Checkpoint: no suds or slippery residue remain on the skin.
7. Dry and protect the skin: Let the horse dry in a warm, clean area. If you use a blanket, make sure the skin is mostly dry first and change the blanket if it gets damp. Checkpoint: the horse is dry and not standing in mud or wet bedding.

Product facts that matter for this routine

• BioHex Shampoo for Cats, Dogs, & Horses: BioHex Shampoo (formerly Hexazole) is a broad-spectrum, antiseptic, soap-free cleansing shampoo indicated for skin conditions responsive to chlorhexidine and miconazole in dogs, cats, and horses. It combines chlorhexidine, miconazole, and MicroSilver BG, and contains Ceramide III to help support healthy skin. The combination of ingredients and the soap-free formula make it a reasonable option when your vet has identified a bacterial or fungal component, and the ceramide is a small bonus for dry or compromised skin.
• Douxo S3 Calm Mousse for Dogs & Cats: DOUXO S3 CALM Mousse contains OPHYTRIUM, a purified natural ingredient selected for high tolerance and a threefold action on the skin's ecosystem. It helps support the skin's physical barrier, supports the microbial flora, and soothes irritated skin. If your horse's skin issue is more about irritation than infection, a leave-on soothing product like this may be part of the plan, though it is labeled for dogs and cats, so ask your vet before using it on a horse.
• Kopertox Thrush Treatment for Horses: Kopertox is recommended as an aid in treating horses and ponies with thrush due to organisms susceptible to copper naphthenate. Thrush is a common bacterial infection of the hoof, especially in wet, muddy, or unsanitary conditions. Skin issues on the lower leg and hoof are often confused with body skin infections. If the problem is in the frog rather than the coat, a hoof-specific treatment is the right tool, not a body shampoo.

Bathing a horse with a skin condition is a skill that improves with practice. Get a diagnosis, use a medicated shampoo correctly, rinse thoroughly, and follow your vet's schedule. If the skin does not improve or gets worse, stop and seek veterinary advice.