Isoxsuprine is a synthetic chemical with epinephrine-Like effects. Its action relates specifically to the walls of arteries which are located in the muscles, internal organs, and extremities. Isoxsuprine causes these arteries to dilate.
INDICATIONS
Isoxsuprine has been used in the treatment of navicular disease and laminitis, where it is presumed that the disease is associated with some degree of decreased blood supply. Isoxsuprine also has been used to relax the uterus during the treatment of uterine infections. In other species, it has been suggested that isoxsuprine can be used to attempt to treat premature labor.
DOSAGE AND ROUTE Of ADMINISTRATION
Isoxsuprine is given orally in a dose ranging from 0.2 mg/kg to 0.6 mg/kg, depending on the treating veterinarian's discretion. This dose is given 2-4 times daily.
SIDE EFFECTS/TOXICITY
The major side effects concern the cardiovascular system. Isoxsuprine causes the systolic blood pressure (e.g., 150/100, the upper number, 150 being systolic) to rise, while the diastolic pressure falls. Reported side effects in other species include nervousness, trembling, weakness, dizziness, palpitations, nausea, and vomiting.
If the horse appears to be developing side effects, consult the veterinarian regarding advisability of stopping this medication, or changing dosage.
DRUG INTERACTIONS
If a horse is receiving isoxsuprine therapy, the veterinarian must know this before treatment occurs with any anesthetic, tranquilizer, or narcotic drug.
PREGNANCY/NURSING
No information is available concerning safety of isoxsuprine use during pregnancy'. Isoxsuprine is known to cause relaxation of the uterus.
DRUG TESTING
ARCI: Isoxsuprine is a Class 4 drug in the ARCI uniform classification system.