Itching and Scratching (Pruritus) in Horses

Key Takeaways

Itching (also referred to as pruritus) in horses is a common symptom that may indicate insect bites, skin infection, or allergic reactions.

• An itchy horse will often rub against other surfaces, including stalls, trees, fences, or buildings, which may lead to loss of hair and more irritated skin

• Itchy horses benefit from prompt veterinary examination

• Diagnostics include a physical examination, bloodwork, and examination of the skin through skin scrapes, biopsy, or hair samples

• Veterinarians benefit from a detailed history of a horse’s itchiness, to help guide diagnosis and treatment

• Treatment depends on the underlying condition, and may include antibiotics, antiparasitics, allergen immunotherapy, or medications to reduce itchiness

A Closer Look: What is Itching in Horses?

Itching is common in horses. While rarely life threatening, itchy horses benefit from prompt veterinary assistance, as itchiness can negatively impact quality of life. Untreated infections may worsen over time, and horses may further irritate or damage their skin by rubbing against rough surfaces trying to scratch themselves. In severe cases, horses may bite their skin causing self-mutilation.

Possible Causes

Itchiness may develop as a reaction to:

• Insect bites

• Parasitic infections, such as lice or mites 

• Fungal infections, such as ringworm 

• Bacterial infections, such as rain rot

• Hypersensitivity disorders such as contact dermatitis or insect bite hypersensitivity (sweet itch)

• Allergic skin diseases, such as atopic dermatitis

Risk Factors

Tail rubbing is a common reaction to itchiness, which may lead to a fraying tail or loss of hair. Horses scratching themselves against objects may also lose patches of fur across their body, or rub out sections of their mane. 

Severe itchiness may cause a horse to scratch more vigorously, which may lead to injury or damage to the skin.

Testing and Diagnosis

A detailed history of itchiness helps focus diagnosis, including

• How long ago itchiness presented

• How regularly it occurs

• Any recent changes to the horse’s life or environment

• Attempted treatments or home remedies

• Animals in contact with the horse during this time

Other diagnostics include 

• A physical exam

• Bloodwork

• Skin scraping

• Examination of hairs under a microscope

• Skin biopsy

• Bacterial or fungal culture

Treatment depends on the underlying cause, and may include allergen immunotherapy, antibiotics, antiparasitic drugs, and medication to reduce itchiness. Preventive measures based on the underlying cause may also be suggested, such as insect repellants, removing allergens from the horse’s environment, or regular deworming.

Similar symptoms

Itchiness is self-evident.

Associated Symptoms

Itchiness may be accompanied by:

• Hair loss

• Hives

• Skin crud