Strange lumps, itching, bald spots, redness, skin flaking, and scruffy patches are common signs of skin problems in horses.

While most equine skin irritations don’t present serious health risks, persistent skin problems can lead to infections and could indicate allergies, systemic inflammation or other health concerns. [1]

Identifying the underlying cause of skin issues is key to alleviating symptoms and preventing recurrence. Bug bites, mud, poorly fitted tack, bacteria and fungi are all common causes of dermatological issues in horses.

This article will review the identification, causes, treatments, and prevention of common skin irritations in horses. We will also discuss how to support equine skin health and manage horses with skin problems.

Common Equine Skin Problems

Equine skin irritations can arise from several different causes, including allergies, parasites, trauma, burns, chemical irritants, or diseases caused by bacterial infections, viral infections, fungal infections, parasites, or allergies. [1]

Skin problems are usually accompanied by dermatitis – a general term that describes skin inflammation. Other signs of irritation include:

  • Hair loss and bald spots
  • Bumps or hives
  • Thickened skin
  • Scaling or dandruff
  • Skin redness
  • Itching and discomfort
  • Skin lesions with or without fluid discharge

Early identification is vital for the effective management of many equine skin diseases. Horses with skin inflammation are at risk of secondary bacterial infections if the skin’s immune barrier function is compromised.

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Causes of Skin Irritations

Here are some common skin conditions that horse owners should learn to recognize.

Rain Scald

Rain scald, or rain rot, is a bacterial skin infection that affects the horse’s rump and back. Dry and scaly skin is the first symptom. In advanced cases, horses develop crusty lesions and scabs with upright tufts of hair. [2]

Under the scabs, raw skin may discharge sticky yellow exudate. The secretion causes hair to matte together. Bald spots and areas of hair loss occur when scabs detach from the skin. [3]

This type of dermatitis can also affect areas of the barrel, shoulders, hindquarters, face, and lower legs.


Rain scald is caused by the bacteria Dermatophilus congolensis. This opportunistic organism is naturally present on the skin and multiplies rapidly in a moist environment. [2]

When excessive moisture weakens the skin’s protective barrier, the bacteria invade the epidermis and result in infectious lesions. [2]


The horse’s skin must remain dry while being treated for rain scald. Allowing the coat to dry out will reduce recovery time and aid the healing process.

Washing the skin with chlorhexidine scrub and soaking it in a saline solution helps remove crusty skin. Some local lesions respond to treatment with topical silver sulphadiazine. In rare cases, your veterinarian may prescribe systemic antibiotics. [2]

Rain scald lesions usually heal without scarring. Mild cases usually subside within two to three weeks.


Horses that live outside in wet conditions have a higher risk of rain scald. Always ensure horses have access to adequate shelter and consider stabling your horse to let their coat dry. Waterproof blankets can also protect horses from excess moisture during turnout. [2]

Rain scald is contagious. Regularly disinfect equipment that contacts an affected horse and avoid sharing brushes with other animals to prevent infection.

Pastern Dermatitis

Also known as scratches, mud fever, or greasy heel, pastern dermatitis refers to multiple conditions that cause skin irritation on the horse’s pastern.

Mild forms of pastern dermatitis cause redness, itchiness, and hair loss. More severe cases involve skin lesions on the pastern and heel that produce oily secretions. [4]

These clini