Rain rot—also called rain scald or dermatophilosis—is a bacterial skin infection that can cause crusts, scabs, and tufts of hair to lift from a horse’s coat. It often appears after prolonged wet weather, but a horse with recurring or severe lesions needs a veterinary assessment because several skin conditions can look similar.
What does rain rot look like?
Early signs may include small raised areas, matted hair, tenderness, or scabs along the back, neck, rump, and other areas exposed to rain. When the crusts loosen, hair can come away in small clumps. Some horses are only mildly uncomfortable; others resent grooming or handling over affected skin.
Rain rot is more likely when the skin stays wet, the coat cannot dry, or insects and skin irritation compromise the skin barrier. It can spread between horses through shared grooming tools, blankets, tack, or close contact. Treat every suspect case as potentially contagious until a veterinarian or experienced professional confirms otherwise.
Can you ride a horse with rain rot?
Usually, postpone riding until you understand the extent of the lesions and the horse is comfortable. Tack can rub sore skin, trap moisture, and contaminate equipment. If the horse has only a small, non-tender area and your veterinarian says exercise is appropriate, use clean, well-fitting equipment, avoid affected skin, and stop if the horse shows pain or resistance. Do not work a horse that is unwell, feverish, painful, or developing rapidly spreading lesions.
How to manage a mild case
- Separate grooming equipment. Label brushes, curry combs, blankets, and towels for the affected horse and clean them before reuse.
- Keep the horse dry. Provide shelter and allow the coat to dry fully. Replace damp blankets and address leaks, mud, and poor drainage around the barn.
- Ask about an appropriate medicated wash. Veterinary guidance may include a topical antibacterial product such as chlorhexidine, povidone-iodine, or benzoyl peroxide. Follow the product label and your veterinarian’s directions; more product or harsher scrubbing is not better.
- Do not forcibly pull scabs. Loose crusts may lift during a properly directed wash, but aggressive scraping can damage skin and increase pain.
- Dry thoroughly. Moisture left against the skin can prolong the problem. Use clean towels and a safe drying area.
When to call the veterinarian
Seek veterinary advice if the horse has extensive lesions, swelling, pus, fever, marked pain, lethargy, eye or facial involvement, repeated recurrences, or no improvement with sensible management. A veterinarian may need to confirm the diagnosis, rule out fungal infection, parasites, allergies, or other dermatitis, and prescribe treatment. Do not share medicated products between horses without professional direction.
Preventing rain rot from returning
Prevention starts with a coat that can dry, clean grooming equipment, and a management system that reduces prolonged wetness. Check blankets for fit and cleanliness, improve shelter and drainage, and inspect the skin regularly during wet seasons. Avoid clipping or bathing more than necessary in cold, wet weather, and never put a blanket on a damp horse unless your veterinarian has given specific instructions.
Related horse-care guides
- How to improve horse barn air quality
- What kind of hay is not good for horses?
- Can horses stay outside in winter?
Sources: Penn State Extension: Rain Rot in Horses; Merck Veterinary Manual: Dermatophilosis (Rain Rot) in Horses.
Related rain-rot guidance
For the transmission question specifically, see Is Horse Rain Rot Contagious? for a focused explanation of spread and stable hygiene.
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