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The Buzz About Insect Bite Hypersensitivity

Insect bite hypersensitivity is a clinical term for bug bite allergy, and susceptible horses are actually allergic to insect saliva. In Wisconsin, this is a common problem during the warm-weather months.

Horses can have allergic reactions to any insect bite, but the most common reactions come from bites from these insects: no-see-ums, gnats, midges, sand flies, black flies, stable flies, horse flies, and mosquitos.

Your horse may have an allergic reaction that includes hives, itchiness, hair loss, dermatitis, or a combination of any of these symptoms.

As with many issues that affect our horses, the best and easiest treatment is often prevention. Keeping your horse and his living area as insect free as possible will help. There are many commercial fly sprays on the market that work very well. We've found it to be very effective to alternate the types and brands of fly sprays: use an essential oil-based fly spray (we like Bye Bye Insects) this week and a spray containing pyrethrin insecticide next week.

Some insects prefer to feed at dusk and dawn, so timing your horse's turn-out to avoid those times of the day can help.

Using a box fan on your horse's stall can help to keep very small insects like mosquitos off your horse because they try to avoid strong air currents.

Routine barn and pasture maintenance such as removing standing water or manure is helpful to disrupt insect breeding patterns and reduce their overall numbers.

Using fly predators or a feed-through fly inhibitor has been effective for some horse owners. This type of product kills flies before they emerge.

Some horses benefit from wearing fly sheets and fly masks.

To break the cycle of itching and hives, it's safe and usually very effective to give your horse one 500 mg dose of Diphenhydramine HCI (Benadryl or a store-brand version). In many cases, this is all that's needed. Topical ointments may also offer your horse relief, as can cool-water rinses and shampoos to remove any remaining allergens from their skin.

Dr. Suzanne also recommends Equishield SA Powder for Skin and Allergy. This product supports healthy skin and immune function and contains some fantastic ingredients such as MSM, vitamin E, and quercetin.

Most horses with insect bite hypersensitivity can be best managed using a variety of approaches that include insect repellants, well-timed turnouts, supplementing to support your horse's immune system, and treating their symptoms of itching and hives. If you feel your horse requires more serious medical attention such as the use of corticosteroids, please call Dr. Suzanne.

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