| Urticaria is also known as nettle rash and it is an allergic reaction of the skin. |
The skin develops raised patches due to the accumulation of fluid in the dermis. The raised patches can vary in size and are painless to the touch but they can be itchy, causing the horse to rub and bite itself. In severe cases the serum may ooze through the skin and the horse can become distressed.
The patches are usually irregularly distributed on the neck, chest and abdomen. The eyelids and muzzle can also sometimes swell.
Causes of Urticaria include:
1. Nettles or other irritants.
2. Fly bites.
3. Parts of the diet eg. barley
4. Some antibiotics.
Treatment depends on the severity of the condition.
Diet - The horse should be put onto a light diet and barley and high performance concentrates should be avoided until the condition has been resolved.
Medication - In severe case the vet may prescribe drugs, such as antibiotics or antihistamines, to help clear up the condition.
If the condition is persistent you should try and pinpoint the exact cause, so the future management of the horse can be adjusted to prevent it being exposed to the allergen and the condition reoccurring.
When a horse is known to have allergic reactions preventative measures should be taken:
• Apply fly repellent
• Do not ride through stinging nettles
• Spray or cut down nettles found on the horse's pasture.
• Use a summer sheet
• Provide shelter form the flies
• Only use proprietary horse shampoos
• If you are using any new products, test them first on a small area of skin.
• Avoid using biological detergents on rugs, numnahs and girths.