Sweet itch is an allergic skin condition in horses that causes persistent itching, rubbing and damage to the mane, tail and surrounding skin. Also called insect bite hypersensitivity, it develops when a horse’s immune system reacts excessively to proteins in the saliva of biting insects, particularly Culicoides midges. A small number of bites can provoke considerable discomfort in a sensitive horse. Sweet itch management focuses on reducing those bites and helping inflamed skin recover. Switch 250ml is a permethrin pour-on medicine authorised as an aid in controlling the condition in horses and donkeys. Its insecticidal and repellent action helps reduce exposure to the insects responsible, alongside physical protection and changes to turnout and stabling during the times when midges are most active.
The first signs of sweet itch may be broken mane hairs, a rubbed tail head or a horse spending longer scratching against fencing and stable doors. Pruritus, the clinical term f...
Sweet itch is an allergic skin condition in horses that causes persistent itching, rubbing and damage to the mane, tail and surrounding skin. Also called insect bite hypersensitivity, it develops when a horse’s immune system reacts excessively to proteins in the saliva of biting insects, particularly Culicoides midges. A small number of bites can provoke considerable discomfort in a sensitive horse. Sweet itch management focuses on reducing those bites and helping inflamed skin recover. Switch 250ml is a permethrin pour-on medicine authorised as an aid in controlling the condition in horses and donkeys. Its insecticidal and repellent action helps reduce exposure to the insects responsible, alongside physical protection and changes to turnout and stabling during the times when midges are most active.
The first signs of sweet itch may be broken mane hairs, a rubbed tail head or a horse spending longer scratching against fencing and stable doors. Pruritus, the clinical term for itching, can become intense enough to interrupt grazing and rest. Repeated rubbing causes hair loss, soreness and small wounds; over time, affected skin can become thickened and folded, a change known as lichenification. Sweet itch often affects the mane crest, withers and tail, although the face, ears, belly and other areas may also be involved. Some horses become irritable or restless because the irritation persists throughout the day. The condition is not contagious, so it does not pass between horses through contact. Several animals at the same yard can nevertheless be affected because they share exposure to biting insects.
Protection from midges is central to managing sweet itch. These insects favour sheltered, damp conditions and are often particularly active around dawn and dusk. A breezier paddock away from wet, muddy areas can reduce exposure, while bringing a horse into a suitably protected stable during peak activity can help. Fine mesh over stable openings and a safely installed fan can make it harder for midges to reach the horse. A well-fitting sweet itch rug gives a physical barrier over vulnerable skin, with neck and belly coverage particularly useful where those areas are affected. Regular checks beneath the rug help identify rubbing, trapped dirt or areas becoming sore. Fit and cleanliness are important because a protective rug should remain comfortable throughout wear. The combination of these measures reduces opportunities for bites across the day.
Switch aids sweet itch control through permethrin, a synthetic pyrethroid insecticide present at 40mg/ml, equivalent to 4% w/v. Permethrin acts on sodium channels in insect nerve cells, disrupting normal nerve function. The product acts externally and has fly-killing and repellent activity; its purpose is to reduce insect exposure that can trigger the allergic reaction. Switch is supplied as a ready-to-use pour-on solution in a 250ml bottle with an integrated measuring chamber. It contains no corticosteroid or antibiotic, and its benefit comes from insect control rather than direct suppression of the horse’s inflammatory response. Weather conditions and the insects involved influence its effect, so treatment cannot guarantee complete protection from every bite. For sweet itch, combining this insect control with physical barriers addresses exposure more thoroughly than relying on one measure alone.
Switch treatment for sweet itch should begin at the start of the season and be repeated as needed, with once-weekly application sufficient for most horses. The measured quantity is divided approximately equally between the mane and rump, leaving the saddle area untreated. It must not be applied forward of the ears, and contact with the eyes must be avoided. Apply it after grooming if the horse is being groomed. The quantity depends on bodyweight and must not exceed 40ml per treatment; use the measuring chamber and the directions supplied with the bottle. Horses with fine, sensitive skin, particularly those of Arab type, can react to the product, and a small patch test at the base of the neck 24 hours before use is recommended for these animals. Stop treatment if irritation develops.
A horse with sweet itch may remain uncomfortable after insect exposure has been reduced because established inflammation and damaged skin need time to settle. Gentle skin care can help keep affected areas clean, while extensive sores, discharge or continuing severe rubbing warrant veterinary treatment. Other causes of itching, including lice and different allergies, can produce similar signs. Sweet itch commonly recurs during warmer months, so beginning protection before substantial rubbing develops gives the skin a better chance of remaining intact. When applying Switch, wear protective clothing, boots and chemically resistant gloves, and work in a well-ventilated area. It is unsuitable for horses or donkeys intended for human consumption. Keep the bottle tightly closed below 25°C, and prevent the liquid or used container from contaminating ponds, streams or ditches.
Sweet itch is an allergic reaction to proteins in the saliva of biting insects, especially Culicoides midges. Sensitive horses develop inflammation and intense itching after bites. It is also called insect bite hypersensitivity and commonly recurs during warmer months when the insects are more active.
Early signs include rubbing the mane or tail, broken hairs and increased scratching against fences or stable doors. The horse may seem restless or irritable. As the condition progresses, hair loss, crusts and thickened skin can develop, with repeated rubbing sometimes causing open sores.
Switch contains permethrin, an insecticide with fly-killing and repellent activity. It helps reduce exposure to biting insects that trigger sweet itch. It is authorised as an aid to control, with protective rugs and changes to turnout or stabling providing additional ways to reduce midge contact.
Switch is a veterinary insecticide supplied as a ready-to-use pour-on solution. It contains 40mg/ml permethrin, equivalent to 4% w/v. Although some listings call it Switch Lotion, it should not be described as a daily moisturiser, skin conditioner or cream that directly treats inflammation.
The product directions recommend starting at the beginning of the sweet itch season and repeating as necessary. Once-weekly treatment should be sufficient for most horses. Weather and the insects present influence its effect, so it should not be advertised as guaranteed protection against every bite for seven days.
Divide the measured amount approximately equally between the mane and rump, avoiding the saddle area. Do not apply it forward of the ears or allow contact with the eyes. Apply after grooming, using the bottle’s measuring chamber and the bodyweight directions, with a maximum of 40ml per treatment.
