Isoxsuprine may increase the heart rate, cause changes in blood pressure, and irritate the GI tract. It should therefore be used with caution if combined with other drugs that affect blood pressure, such as sedatives and anesthetic drugs.
Isoxsuprine is most commonly used to treat hoof-related problems in the horse, most commonly for laminitis and navicular disease, as its effects as a vasodilator are thought to increase circulation within the hoof to help counteract the problems associated with these conditions. Isoxsuprine is given orally, and many horses find the pills quite palatable. Isoxsuprine is a prohibited class B drug in FEI-regulated competition, and is often prohibited by other equine associations. It may be detected in the urine for several weeks or months following administration. It is therefore important to check the drug-rules within an animal's given competitive organization, before administering the drug.
Because it is a vasodilator, it should not be used in horses that are bleeding, or in mares following foaling.
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