Horse Sweet Itch Prevention and Care

Sweet itch (insect bite hypersensitivity) causes severe seasonal pruritus in susceptible horses; targeted management significantly reduces suffering.

Key Facts

Sweet itch is caused by hypersensitivity to the saliva of Culicoides midges, which bite most actively at dawn and dusk.
Approximately 5% of horses in the UK are affected to some degree.
Susceptibility has a heritable component; certain breeds including Icelandics and Irish Draught types are predisposed.
Affected horses rub mane and tail bases, causing hair loss, skin thickening, and open wounds.
Full-body Boett rugs that prevent midge access reduce symptoms significantly when used consistently.

Welfare Considerations

Sweet itch causes intense, chronic pruritus that significantly impairs welfare during the midge season (April-October). Affected horses may rub continuously, causing extensive self-trauma, raw skin, and secondary bacterial infections. The condition is distressing to observe and to manage; owners often feel frustrated by the limitations of available treatments. Corticosteroids reduce inflammation but have significant side effects with long-term use. Insect-proof rugs and stabling during peak midge activity (dawn and dusk) are the most effective management strategies. New immunotherapy approaches are in development and show promise for disease modification.

What You Can Do

Stable affected horses at dawn and dusk during the midge season to reduce exposure.
Use a well-fitting Boett or similar full-body midge rug as the primary physical barrier.
Consult your vet about corticosteroid use for severe cases — short-term use can break the itch-scratch cycle.
Contact your vet about immunotherapy trial participation if your horse is severely affected.