Isoxsuprine (used as isoxsuprine hydrochloride) is a drug used as a

vasodilator Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, ...

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

s (under the trade name Duvadilan) and

equine Equinae is a subfamily of the family Equidae, which have lived worldwide (except Indonesia and Australia) from the Hemingfordian stage of the Early Miocene (16 million years ago) onwards. They are thought to be a monophyletic grouping.B. J. MacFa ...

s. Isoxsuprine is a β₂ adrenoreceptor agonist that causes direct relaxation of uterine and vascular smooth muscle via β₂ receptors.

Use

In humans

Isoxsuprine is used in humans for treatment of premature labor, i.e. a

tocolytic Tocolytics (also called anti-contraction medications or labor suppressants) are medications used to suppress premature labor (from Greek τόκος ''tókos'', "childbirth", and λύσις ''lúsis'', "loosening"). Preterm birth accounts for 70% ...

, and as a vasodilator for the treatment of cerebral vascular insufficiency,

Raynaud's phenomenon Raynaud syndrome, also known as Raynaud's phenomenon, eponymously named after the physician Auguste Gabriel Maurice Raynaud, who first described it in his doctoral thesis in 1862, is a medical condition in which the spasm of small arteries cau ...

, and other conditions. 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

sedative A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but t ...

s and

anesthetic An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia ⁠— ⁠in other words, to result in a temporary loss of sensation or awareness. They may be divided into two ...

drugs.

In horses

Isoxsuprine is most commonly used to treat hoof-related problems in the horse, most commonly for

laminitis Laminitis is a disease that affects the feet of ungulates and is found mostly in horses and cattle. Clinical signs include foot tenderness progressing to inability to walk, increased digital pulses, and increased temperature in the hooves. Sever ...

and

navicular disease Navicular syndrome, often called navicular disease, is a syndrome of lameness problems in horses. It most commonly describes an inflammation or degeneration of the navicular bone and its surrounding tissues, usually on the front feet. It can lead t ...

, 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.

References

{{Ionotropic glutamate receptor modulators Secondary alcohols Amines Beta-adrenergic agonists Equine medications NMDA receptor antagonists Phenol ethers Phenols Phenylethanolamines Vasodilators