Have you noticed any strange lumps and bumps when grooming your horse lately? Or any areas that are particularly itchy? It could be Sweet Itch! These scratchy lesions are quite common. In fact, one study found that 20 percent of horses examined suffered from this summertime affliction. Also known as allergic dermatitis or culicoides hypersensitivity, these lesions cause your horse significant discomfort that may include itching, hair loss, swelling, and infection. 

Got questions? We’ve got answers! Keep reading to find out what causes Sweet Itch and how you can manage this uncomfortable condition. 

Causes of Sweet Itch in Horses

While horses can have an allergic reaction to any insect, the most common source of insect bite hypersensitivity in horses are culicoides, also known as no-see-ums, midges, or gnats. Like mosquitos, culicoides are small flying insects that feed on the blood of mammals. Just after the bite, an inflammatory response occurs leading to swelling beneath your horse’s skin and an increase in white blood cells in the area. If the swelling becomes too severe, the lumps will burst open into small crusty scabs. 

These uncomfortable scabs and lumps are most often found along your horse’s ventral line (under their belly), in their mane and tail, and along their ears. It’s important to get on top of this allergic reaction quickly, otherwise your horse could become trapped in a downward spiral. For example, the first time your horse gets Sweet Itch, it may not be so bad. But as the horse starts scratching, he begins to lose his protective hair coat, exposing more skin to midges, which offers more opportunities for bites.

Break the cycle as early as possible through the use of good stable management practices and medical intervention to avoid causing your horse additional discomfort. Get in the habit of examining your horse’s legs, belly, and ears daily for signs of Sweet Itch. 

Stable Management Practices to Combat Sweet Itch in Horses

You can manage your barn to limit your horse’s exposure to culicoides pretty easily. Luckily, these midges have several weaknesses that you can use to your advantage. 

These weak insects only fly short distances and not against a breeze. They’re often found in stagnant water and are most active at dusk and dawn. Manure piles create the perfect breeding environment for these little midges.

You can significantly decrease the population of culicoides at your barn in just a few steps. Pick your paddocks and stalls often to remove manure. Dragging your turnout areas can also be helpful to break up and dry out manure piles, making them inhospitable to midges. Store all manure as far away from stalls and pastures as possible to encourage the culicoides to stay away from the area. Remove as many sources of stagnant water as possible. If you’re unable to remove water sources, change the water frequently to avoid creating a breeding ground for culicoides. While it’s always important to clean water troughs and buckets often, be sure to change the water even more frequently from March to November when culicoides are particularly active. 

Protective fly equipment such as masks, boots, and a sheet protect your horse against culicoides bites. Be sure to use well-fitted gear that won’t cause your horse to overheat or develop rubs. If it’s too hot to use a fly rug in your area, try using a barrier cream to protect your horse’s skin, instead.

A high-quality barrier cream does exactly what its name implies-- it provides a protective barrier between your horse’s skin and external irritants like culicoides. Zarasyl doesn’t just protect your horse’s skin from midges, it also contains orthosilicic acid known to promote healthy connective tissue growth and nourish the skin at the same time.

How to Manage an Active Culicoides Reaction

Despite your best efforts, your horse may still develop Sweet Itch. That’s okay-- what’s important is to act quickly to relieve your horse’s discomfort and get on top of the reaction before it worsens. Changing your stable management routines, using protective fly gear, and applying a barrier cream will heal most mild reactions to culicoides. More severe reactions may require steroids in order to heal. 

If your horse develops Sweet Itch, consider stabling them at dawn and dusk with a box fan to limit exposure to culicoides. Start using a fly sheet, fly mask, and fly boots if you aren’t already. Look for a fly sheet with a belly flap to protect the most sensitive areas of your horse’s body. If possible, shorten the time frame between cleaning stalls or picking paddocks to limit the amount of time manure is near your horse.

Last but not least, use a barrier to cream to manage active Sweet Itch reactions and to avoid future ones. Check out our veterinarian and customer testimonials to hear about the success others have had when using Zarasyl to manage active Sweet Itch in horses.

Key Takeaways:

1. Sweet Itch is an allergic reaction caused by culicoides, also known as no-see-ums, midges, and gnats. 
2. Signs of Sweet Itch in horses include itchy lumps or scabs along the belly, ears, and legs. 
3. Good stable management practices such as removing manure from your horse’s environment as quickly as possible, using protective fly gear, and removing stagnant water will minimize the population of culicoides on your farm. 
4. A high-quality barrier cream, like Zarasyl, adds a protective layer between your horse’s skin and external irritants like culicoides. Check out our Veterinarian Testimonials on our homepage to hear about their success when using Zarasyl to manage active Sweet Itch reactions.