While spending time in a pasture can work wonders for your horse’s mental health and well-being, if you live in an area with wet or humid weather conditions, your horse could be susceptible to a skin disease commonly known as “rain rot.” Rain rot is neither life-threatening nor career-ending, but it is painful for your horse and can cause long-term damage to their skin and hair. You care about your horses, so here is everything you need to know about rain rot—from detecting it early on, to treating active cases, and preventing it all together in the future.


What is rain rot in horses? We’ll address that question first for our comprehensive look at rain rot treatment and prevention.

What causes rain rot on a horse?

Rain rot, technically known as dermatophilosis, is a common equine skin disease caused by a bacterial infection. The source of this infection is a bacterium known as Dermatophilus congolensis, which lies dormant in the outer layer of the horse’s skin. When the horse’s skin becomes compromised—either by prolonged exposure to high humidity, high temperatures, wetness, or biting insects—and D. congolensis reaches the compromised skin site, the bacterium produces hyphae (threadlike tentacles) that penetrate the skin and spread in all directions. The result is an acute inflammatory skin response. Both internal and external conditions affect and enable the bacterium to multiply. In fact, the risk for contracting rain rot is amplified when a horse suffers from a weak immune system, a damaged skin barrier, poor nutrition, poor hygiene, or other stressful circumstances. Often mistaken for a fungal disease, the condition can be characterized by the development of crusty scabs that peel off, removing clumps of hair with them, and resulting in bare spots on the horse’s skin.

When and where does rain rot occur?

As mentioned before, warm temperatures, heavy rainfall, humidity, and insects all contribute to ideal growing conditions for the bacterium. Insects can spread the infection from horse to horse, and the number of insects usually increases with warmer temperatures and increased humidity. Spring and summer seasons provide a fertile environment for bacteria to thrive, what with rain and warm temperatures. However, rain rot can also occur in the wintertime, especially in southern states. If temperatures rise and fall, causing your horse to sweat under a blanket, that warm, moist environment creates optimal breeding grounds for the bacterium. Typically, you’ll spot rain rot along the horse’s dorsal surfaces, which include the croup, neck, back, and hindquarters. These are the parts of the body most vulnerable to weather. Horses or ponies with thick coats are more likely to keep leftover moisture from the rain close to their skin and are therefore at higher risk of contracting rain rot.

Is rain rot in horses contagious to humans?

Though rain rot treatment is simple and essential, it can also be dangerous because rain rot is highly contagious to other animals, as well as humans. Any grooming tools, brushes, buckets, or blankets that come in contact with an infected horse should be thoroughly cleaned and not shared with other horses. To prevent further contamination, scabs should be discarded into the trash or burned, as they still harbor contagious bacteria. Infected horses should also be kept separate from other animals.

Detecting rain rot

There are a few tell-tale signs of rain rot, and they are not too difficult to detect. A number of hours after coming in from the rain, your horse’s coat may be matted into tufts or irregular patterns, with their skin radiating heat and flinching at your touch. You will begin to notice skin lesions or tight scabs along the horse’s back and sides, where moisture was concentrated. The scabs themselves should not be painful for your horse, but they can definitely cause pain if you attempt to remove them. Once you suspect rain rot, begin treatment immediately. The sooner you can detect rain rot, the sooner you can treat it and spare your horse extended discomfort and serious cosmetic problems.


How do you treat rain rot in horses?

Rain rot treatment will remain the same throughout the seasons; however, it may be more prevalent or rigorous during certain times of the year, depending on where you live. Here is our step-by-step guide for treating active cases of rain rot:

  1. Take a deep breath and show your horse some love. We promise it will be okay.
  2. On Day #1, apply Equiderma Skin Lotion on and around the location of all scabs visible on your horse’s skin. Be sure to apply lotion liberally against the direction of the coat.
  3. n Equiderma Skin Lotion is a scab-removing champion. Apply it on the first day and leave it on. Do not pick the scabs. Equiderma will take care of them for you. It’s fast-acting, easy to apply, and will not sting or burn your horse. It is scented with lavender essential oil—your horse’s aromatherapy favorite. Let them take a whiff before application, as they will be much more cooperative in the process. n
  4. On Day #2, gently shampoo your horse with Equiderma Neem Shampoo. Not only will it thoroughly clean your horse, but it will hinder the bacteria from multiplying.
  5. Lather the shampoo and let it sit for at least 10 minutes, or up to one hour before rinsing
  6. As you rinse, you’ll notice the Equiderma Skin Lotion has softened the scabs and they rinse away easily.
  7. Re-apply Equiderma Skin Lotion
  8. Repeat application daily until you notice hair regrowth and a cessation of infection and inflammation. Equiderma Skin Lotion works quickly, so this process should happen within a day or two.

How do you treat rain rot naturally?

When it comes to treating rain rot in horses, home remedies can provide an attractive natural solution. However, when it comes to homemade treatments, remember to proceed with caution, as some “treatments” out there can actually exacerbate issues and cause your horse more discomfort. It is always wise to consult with a vet for diagnosis and treatment, as well as for verification of the effectiveness of home remedies.

Baby Oil and Peroxide

In a bucket, mix 16 ounces of mineral or baby oil, 16 ounces of 3% USP hydrogen peroxide, and a half-ounce of tincture of iodine. This concoction will work to soften and eventually lift the scabs, as well as soothe the horse’s skin, and kill the bacteria. Wash your horse the following day with a mild shampoo and let them air-dry in the sun. Do not keep this mixture in a sealed container, as it will bubble up and explode.

Oils and Sulfur

Another homemade rain rot salve involves combining a large bottle of baby oil, tea tree oil, rosemary oil, and powdered sulfur. You can mix these together in the baby oil bottle or a bottle with a sprayer. Add ten drops of the tea tree and rosemary oil, and just enough sulfur powder so that when it settles, there is about half an inch at the bottom of the bottle.
During recovery, keep the affected area clean and monitor the skin lesions closely. Do not cover them with any equipment that might expose affected areas to dirt, or reopen wounds.


Preventing summer or winter rain rot before it happens

The very best form of rain rot treatment for the future is careful prevention. Practicing good hygiene and removing environmental factors that put your horse at risk are the most effective ways to do so.

  • During rainy seasons, be sure your horse has access to shelter.
    • Avoid heavy blankets. Instead, use a breathable sheet as protection from the rain.
    • Clean all tack and equipment, and take a break from riding if you notice lesions developing in the saddle area.
    • Groom your horse with clean brushes, scrape excess water off their body after a bath and make sure they dry completely.
    • Apply insect repellent regularly during seasons with more bugs.

If your horse is prone to rain rot at certain times of the year, apply Equiderma Skin Lotion at those times and leave it on to destroy dermatophytes living on your horse’s skin. We also suggest that you:

  • Keep your stable/barn clean and well ventilated.
  • Avoid sharing blankets, brushes, and saddle pads between horses.
    • Disinfect any shared equipment.
  • Regularly check blanketed horses for sweat.
    • Change blankets regularly if the horse is prone to sweating.
  • Cool off a sweaty horse completely before blanketing.
    • Polar fleece/wool coolers encourage wicking and can be used under waterproof sheets.
  • Pasture mud management—it’s a must!
  • Give your horse some sun.
    • Sunshine is an important support for skin diseases and helps kill bacteria and fungus.
  • Supplement your horse’s diet with a multivitamin and mineral supplement.
  • Good nutrition will promote proper skin vitality and health.

With these tips, you are on your way to a healthy and happy horse. For the best arsenal against rain rot and other conditions, shop Equiderma products today!


Recognizing the Signs of Colic in Horses [What You Need to Know]

The connection between horse and human can be almost supernatural, so when...


Riding Accident

How many of us have heard this saying?  “You’re not a rider...


Diagnosis, Treatment, and Prevention of Lyme Disease In Horses

Lyme disease is often confounding because the symptoms can mimic so many...