Epinephrine is used in horses as a treatment for shock, anaphylaxis, and in cardiac resuscitation. Because of its vasocontrictive properties, epinephrine is also added to local anesthetics to retard systemic absorption and prolongs their effect. This article is about the contraindications, toxic effects, dosages, and association drug rules that apply to this medication.

Epinephrine is an adrenergic agent that has both alpha and beta adrenergic activity. It relieves bronchoconstriction, increases blood pressure, stimulates the heart, raises blood sugar, and antagonizes histamine. It is used to rapidly counteract severely allergic (anaphylaxis) reactions to drugs, vaccines, insect bites. Anaphylaxis in the horse is characterized by any combination of hives, sweating, edema, colic and difficult breathing. Symptoms usually begin shortly after administration of an injection. Difficult breathing is the hallmark of a severe allergic reaction. Early aggressive treatment may be required.