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How to Manage Rain Rot in Horses: Symptoms, Treatments, and Cures

Julia Everheart is a 31-year-old who never grew out of her adolescent horse-crazy phase.

Rain Rot in Horses

Rain Rot in Horses

What Is Rain Rot or Rain Scald in Horses?

Rain rot, also known as rain scald, is a bacterial skin infection that is common in horses. The correct veterinary term for the condition is dermatophilosis, and it is caused by a bacterium called Dermatophilus congolensis. It most commonly occurs in humid, wet weather.

Rain rot thrives in a moist, warm atmosphere and is more common in the spring and summer when the rains and higher temperatures provide a breeding ground for this nasty bacteria. It also crops up in winter, especially if temperatures rise and fall and horses are sweating under their blankets as the temperatures get warmer throughout the day.

The condition is awfully hard to get rid of once a horse has developed it, so we will look at how to prevent it as well as how it's treated.

What Does It Look Like?

Rain rot in horses looks similar to mange in dogs, but is not the same thing and cannot be managed the same way. This condition can be a sign that a horse is not being cared for properly, but this is not always the case as some horses have sensitive skin and are more susceptible. Horses in the American South are also more susceptible simply because the weather is hotter.

Signs of Rain Rot

  • Hair loss
  • Hair that rises up in tufts
  • Hair that falls out if rubbed or brushed
  • Smooth skin underneath hair loss (mild cases)
  • Small scabs or sores (severe cases)
Equine hair loss due to rain rot.

Equine hair loss due to rain rot.

How to Prevent Rain Rot in Horses

First, prevention is key! If your horse is living in a pasture setting and has a run-in shed but no enclosed stall, he or she will get wet. Horses don't seem to mind the rain like people do, so your horse is likely to stay out in the open under light rain. This is okay. Many horses seem to be the happiest living outside 24/7, so don't feel like you need to run out and put your horse in the barn every time it sprinkles.

Mud Exposure Is a Huge Risk Factor

If he or she rolls in the mud, however, try to get them cleaned up pretty quickly. The bacteria that causes rain rot is believed to be found in dirt. If your horse has had rain rot in the past and seems particularly susceptible to it, you may have to resort to keeping them stalled and dry in wet weather. Essentially, keeping your horse as clean as possible is your best defense.

Be sure to disinfect your grooming supplies between use.

Be sure to disinfect your grooming supplies between use.

How to Manage Mild Cases and When to See a Vet

Now, if your horse already has a case of this nasty stuff, you have to determine how bad it is. Does your horse have raw-looking skin or sores where the hair has fallen out? If they do, you need to call your vet.

Putting medicine on raw skin can be terribly painful, so you want to see your vet before you put anything on your horse that could make the problem worse. Antibiotics are usually prescribed in severe cases to help a horse fight off the bacteria.

What to Do If You Cannot Get Your Horse to a Vet

If your horse's hair tufts up and falls out when you scratch it, but the skin underneath is smooth and not irritated, this is likely a mild case of the condition. If you are unable to have a vet out to see your horse immediately, you have several options:

Equine-Approved Anti-Bacterial Spray

  1. Acquire an equine-safe anti-bacterial spray per your vet's recommendation from your local shop.
  2. Take your fingers and brush the affected hair. A curry comb will work as well. (The sooner the hair falls out, the sooner your horse can start new hair growth.)
  3. Brush and spray, brush and spray. (Do this every day!) Brushes, combs, saddle pads, blankets, and the like should all be washed immediately to avoid spreading the bacteria.

If the hair doesn't come out easily, don't force it. Just spray the area. When it's ready to come out, it will, with very little effort.

M-T-G Spray

You can also use M-T-G spray if the skin is not broken. It's about $16 for a spray bottle. It is sulfur-based and smells awful, but will work to kill the bacteria.

  1. Remove the affected hair and spray the area.
  2. Clean everything that comes in contact with your horse to prevent the spread of the bacteria. Brushes, combs, saddle pads, blankets, and the like should all be washed immediately.
  3. I soak my brushes in diluted bleach water. It doesn't hurt the brushes, but it will kill rain rot for sure.

How Soon Will It Go Away?

Rain rot looks nasty and is a pain to get rid of because it tends to spread quickly. In the grand scheme of horse illnesses and injuries, however, it's pretty mild. Yes, your horse will have some bald patches, but they will recover within a couple of months as long as you're vigilant about caring for them. Take heart, it could be much worse!

If for any reason your horse's condition is worsening, see your veterinarian right away.


This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.


Kathy Anderson on July 17, 2016:

We have an antimicrobial spray that is easy to use, very effective and safe. Called Resolve, it was originally developed, tested and approved for the US military as an antimicrobial spray for fungal infections. Check out our testimonials on our website. All you need to do is spray the infected area once a day (many folks tell me even every other day will work) and see it start to work in 2-3 days (many see it in one application). No shampooing, no soaking, no clipping or pulling off the scabs. Works in scratches, thrush, sweet itch, etc.

craig on September 13, 2015:

how often do you apply the listerin and for how long?

Spiritmare on April 24, 2015:

I found this site while searching for help with rain rot. Hope there is still a following here. Last year one shampooing got rid of the rot but this year...My mare is just prone to get it and I am looking for ways to help her out. She had cut her wither rolling three weeks ago and I guess that was the floodgate for this years mess. Plus we have had a lot of rain and higher than usual temps though it is cool at present. Her hide is so sensitive she doesn't want me working on her. Is there an oil I can use on her between shampooing to soften the hide to help with the sensitivity so I can work on clearing up her coat. Or which product is best to clean rain rot with? I have EquiShieldCK at present but it doesn't seem to do as well as I would have hoped. And for future rain rot avoidance, would keeping her in a waterproof turnout sheet help? My horses are out on pasture with a run in. I live in a humid area, north middle TN, and the mare is a thoroughbred. I would appreciate any feedback as I am pretty much on my own and I am a 56 year old who took on rescues.

Ken Halleck on August 09, 2014:

I would say that spraying down your tack and saddle with generic Listerine would help prevent it's spreading, too

Jamie on May 07, 2013:

I have owned my horse for 3 years now. He has never had an episode where he lost hair with balding. I bought the MTG, it's a bit pricey, but after the first day, his skin is clean. He as not access to running water so I bought a cleaning spray where you do not have to have water. It did great! But I brush, brush, brush to get the bad hair out. His new hair is coming in. I feel bad for him...felt like I am neglecting him, but I have taken action quickly. I have washed all his combs, brushes, halters, and lead ropes, even saddle blankets, I have even used a bit of chlorine and water to wipe down his saddle and followed up with anti bacterial dawn soap to clean the saddle. I feel pretty confident. We have been getting so much rain. He likes to go into the pond which doesn't help! and he is a roller!! GRRRR...

Jmillis2006 from North Carolina on March 13, 2013:

My thoroughbred use to get rain rot really bad and I always used mouthwash it works wonders. Great hub.

Freela on September 18, 2012:

If u put m-t-g or minaret oil one it works really well we use it all the time

Tammy on September 03, 2012:

Just bought two bottles of feneric Listerine for my gelding, who got rain rot last year and again this month.

vicky on September 02, 2012:

thanks i wasn't sure how to treat this condition either, thanks for info,

is there anything else that is a natural treatment?

Maddymoomins from Anglesey on August 26, 2012:

My small Shettland has got rain rot on her ear, and your Listerine advise sounds good so i will definitely be trying. Thanks everyone!

Michele on June 29, 2012:

What do you wash the saddle blanket with ?

Amber on April 24, 2012:

Thanks a lot, my horse got rain rot for the first time ever this year and i wasn't sure what to use to treat it, thanks everyone!

juliaeverheart (author) from Kennesaw, GA on April 24, 2012:

Another good product to use is Selsun Blue dandruff shampoo. If you buy the generic version, it's cheaper. I used this once the rain rot was mostly cleared up and the hair was just starting to grow in. It kept my horse's skin from drying out from being exposed.

karmicfilly from Franklin, TN on April 23, 2012:

The research I've done shows that Chlorhexdine is the best to use in a wash/solution which treats the wounds if any and the bacterial factors. Have you ever used this one? I have heard others use Captan Powder which is for fungal infections? I have 1 out of 5 horses who consistantly gets rain rot even though all are treated the exact same way. Every year I know I will be fighting this with him and have gotten use to it. The Listerine has Ethanol in it which is what I assume kills the bacteria. Seems it would be expensive to do an entire horse with that product but I may just have to try it. Thanks for the information.

juliaeverheart (author) from Kennesaw, GA on April 13, 2012:

Yes, Listerine the mouth wash is the thing that I've found works best. The original gold colored Listerine is what I heard I should use, and sure enough, it cleared up rain rot quickly on my horse.

Katie on April 11, 2012:

When you say listerine, do you mean the mouth wash? Thanks