Treating Scratches in Horses (Pastern Dermatitis)
- What are Scratches in Horses?
- Treating Scratches on a Horse's Legs
- Preventing Pastern Dermatitis
- Video on Understanding Scratches in Horses
Updated June 11, 2025
What are Scratches in Horses?
Scratches is a relatively common skin disease of the heels and back of the pastern. Also known as "greasy heel," "mud fever," and "dew poisoning," veterinarians may refer to it as pastern dermatitis or pastern folliculitis.
Repeated wetting and drying of the skin in this area seems to lead to the condition rather than infection by one particular organism, although bacteria and fungi are usually involved. Early on, the heels and pastern may be reddened, warm, and ooze a small amount of yellowish, watery liquid (serum).
As the condition progresses, hair is lost, the area becomes thickened, and hard crusts or scabs of serum form. The condition is painful to the touch and may even cause the horse to become lame.
Treating Scratches on a Horse's Legs
A veterinarian should diagnose the condition so that other diseases can be ruled out and appropriate treatment may start. All crusts, scabs and dead tissue must be removed from the skin before healing can begin, but this must be done gently and with only mild soap, if needed. Avoid using harsh scrubbing and chemical products. The horse's hair on the legs may need to be clipped away from the affected area.
Ointments that have been recommended for scratches include antibiotics, antifungals, steroids and other medications. These should only be applied on the advice of a veterinarian and only on clean, dry skin.
Preventing Pastern Dermatitis
Standing in muddy paddocks, grazing in wet pastures, and frequent bathing all weaken the skin's natural protective barrier and set a horse up for scratches. If the horse cannot be kept in a dry environment, then a light barrier cream, such as petroleum jelly, may be applied to the pastern and heels before exposure to wet environments.
Horses with long leg hair or feathers may benefit from removal of this hair so that moisture and contaminants are not trapped against the skin.
Video on Understanding Scratches in Horses
Watch this video as Dr. Lydia Gray explains how scratches may develop, what owners can do to help ease their horse's discomfort, and ways to prevent scratches from forming.
SARAH: How do you treat and prevent stubborn cases of scratches?
DR. LYDIA GRAY: Oh scratches. You can tell they're frustrating.
SARAH: Especially, well, you live in, Illinois, so you guys are dealing with some pretty serious mud.
DR. LYDIA GRAY: The Midwest. Scratches are a national problem, universal problem, but it turns out that they're different in different parts of the country. In Arizona, they have sand scratches or something.
SARAH: Sounds painful.
DR. LYDIA GRAY: I know. Scratches can be painful. There's a range. We're talking about the pastern of the horse-- just to back up a little bit here-- the back of the pastern, so between the heel and the ankle. You with me? OK. So it can get just a little bit warm, pink/red. Or it can break out in scabs and fluid and hair loss. And it can be painful, so when the horse moves, it hurts.
SARAH: Because it's a really high motion area with the joint flexing there.
DR. LYDIA GRAY: Yeah, and so you're moving that area. It's not comfortable. So does it happen because of an infection, or does it happen because of environment, like chapping-- wet-dry, wet-dry, wet-dry-- probably because the organisms involved can be different in different parts of the country, and treatments are all different. Probably it starts with the opportunity of a break in the skin because of the environment. And then, bacteria that live there normally say, what the heck? We may as well. So they're pals. And then, all heck breaks loose. And so the important thing that I tell people is don't add to the wet-dry, wet-dry by soaking or using excessive water or harsh soaps to clean, picking the scabs off. Do what your vet tells you, and this is an area I would involve my vet right away. But I like to clean as dry as possible. I use something called Dermacloths because it's not water. I don't get them wet, and then, they don't get dry and then just make it worse, a vicious cycle.
SARAH: And where do you buy your Dermacloths?
DR. LYDIA GRAY: From SmartPak.
SARAH: It's the right answer.
DR. LYDIA GRAY: So I clean it. And then I put whatever lotion, potion, ointment that my vet recommends. And again, that's different in different parts of the country. If you find something, a cleaner or a topical that works, buy stock in it, use it. Don't keep switching around because I've got people in Indiana, Illinois, Michigan that like this product, and I got people in Arizona, New Mexico, California that like this product. So--
SARAH: And different horses may respond differently as well.
DR. LYDIA GRAY: Different horses and different colors of horses and breeds. Look at draft horses with the feathers. So one tip is you've got to clip or shave, I'm sorry, all the hair off because to allow healing without further damaging the skin. You've got to air--
SARAH: But you want to do the right thing--
DR. LYDIA GRAY: --air and sunlight.
SARAH: --for the horse.
DR. LYDIA GRAY: Yeah. So it'll grow back. It's fine.
SARAH: It will.
DR. LYDIA GRAY: Yeah, trust us.
SARAH: It always does.