Sweet itch

These information sheets are provided for your interest. They should not replace veterinary advice from your veterinary surgeon.

Whilst every effort is taken to ensure the accuracy and completeness of the information provided, your specific circumstances must be discussed before advice can be given.

Sweet itch “culicoides hypersensitivity”

Sweet itch, a relatively common recurrent seasonal disease, but not all horses are affected. The more commonly affected breeds are cob types, rather than Thoroughbreds. Some horses will suffer more severely than others. Summer is the worse time of year for these horses, but signs can be seen from late spring to early autumn.

The horses are allergic to the insect saliva, which results in the over the top reaction by the skin leading to swellings and itchiness. This is similar to Hay Fever in humans, just that with horses it is their skin that reacts.

Sadly as this is an allergic skin disease it cannot be “cured” but there are many management tools to help your horse through these months.


·         Persistent want to scratch

o   Rubbing their bottom and neck on stable doors, walls, fence posts and people

·         Damaged mane and tail head hair and bald areas of skin

o   Can affect belly and groin area too!

·         Saliva marks on coat where the horse has attempted to chew at the affected area

·         Skin damage and sores if rubbing is severe







·         Poor coat, main and tail condition

·         Behavioural changes

o   Miserable, hard to ride

·         Condition and weight loss

o   Spending too much time trying to avoid the flies than eating

·         Secondary skin infections if the skin is damaged from rubbing

·         Could affect the results of a pre purchase vetting


·         Your horse         

o   Fly rugs – full body (boett blankets) including neck and belly

o   Fly masks

·         Environment

o   Keep horses stabled when the midges are most active – dawn and dusk

§  E.g. stable from mid-afternoon to mid-morning  in the summer months

o   Keep horses from high risk areas – woodland, ponds, streams and wet land

o   If stabled – fly sheet over the door, fans to get the air moving (midges need still air to fly!)

·         Fly repellents

o   There are many different products and you must test them on a small area of your horse’s skin before applying fully. Make sure they have no reactions to the repellent!

o   Examples such as; SWITCH and Deosect

·         Veterinary

o   If you are still struggling to control your horse’s itch, then call your vet! There are some medications that can help reduce the itch.

o   Your vet will prescribe a course of antibiotics if there is an infection present.

§  Infection will not be present in all cases.

Remember that management is the most important factor! Get in touch if you have any worries or would like some management advice.