What is Sweet Itch?
Sweet itch is essentially an allergic skin condition. It is caused by a hypersensitivity reaction to the bite of the Culicoides midge and also certain horse flies. Certain horses are overly sensitive to the saliva of these pests and irritation and intense itching occurs at the site of the bite. Self- inflicted damage will occur as the horse scratches himself.
Signs and symptoms of Sweet Itch
- Intense skin irritation in the mane and tail regions of the horse
- Irritation in the summer months
- Itching and discomfort in the early morning and late afternoon
- Intense rubbing against trees or fences
- Swishing of the tail
- Damage and swelling or wounds around the horses ears, poll, mane, withers, rump, and tail head (less common around the horse’s face, chest, and belly)
- Hair loss over the affected area (often the mane and rump)
- Bald, red, inflamed skin, that may have crusting and sores
- Chronically thickened, blackened, and wrinkled skin
- The bites cause a local allergic reaction with the development of papules and pustules
What Causes Sweet Itch?
The saliva of the midge is the principle culprit. Apart from Culicoides midges other fly and parasite species have been associated with similar hypersensitivity reactions including the stable fly, horsefly and the black fly, as well as no see ums. Some horses may have a genetic predisposition to the disease. Conditions related to intense itching may also include lice infestation, chorioptic mange, rain scald, ringworm, food hypersensitivity and dermatitis.
Diagnosing Sweet Itch
If you notice the signs outlined above, it is important to get a proper diagnosis of sweet itch from your vet. Your vet may decide to take a skin biopsy or carry out some intra dermal skin allergy tests to make a definitive diagnosis of sweet itch.
Help for Sweet Itch
Corticosteroids remain the most useful product for treating and controlling the skin allergy caused by midge bites and other pesky bugs such as gnats and parasites. However with all usage of corticosteroids they can increase the risk of inducing laminitis in the horse. As steroids do have side-effects in horses, they must only be prescribed by a vet – they are very potent anti-inflammatories that may stop the itching and allow the skin to heal, but may also cause side effects. Anti-histamines are used but results are not guaranteed.
There are many natural herbal and homeopathic remedies that can help to sooth angry irritated skin. Borage is a well-known herb high in gamma-linolenic acid (GLA). This herb has been studied for its supportive effects on the skin and can help to support the production natural oils in the horse coat that naturally soothe irritation and itching.
Horsetail has also been approved as an aid to wound healing by the German Commission E expert panel, while herbs such as Dandelion, Rosemary and Kelp can help to strengthen the immune system while nourishing the skin from the inside out.
Spirulina is a rich source of nutrients, containing up to 70% protein, B-complex vitamins, phycocyanin, chlorophyll, beta-carotene, vitamin E, and numerous minerals – helping to add nutrient value to a horse’s diet.
Tagetes minuata (Khaki Bos) is an herb native to South Africa and is used by locals to discourage pests and flies – as a natural bug repellant. The added bonus of natural remedies, of course, is a stunning shine without the risk of side effects!