The drug of choice for the treatment of anaphylaxis is epinephrine, which soothes spasmodic bronchi, thereby relieving laryngeal edema or dyspnea due to airway spasm. In addition, it constricts small peripheral blood vessels and counteracts allergic reaction mediators. Epinephrine can be applied intramuscularly before intravenous access has been opened and can be repeated if necessary. Other drugs such as glucocorticoids, antiallergic or antihistamines can be used to treat anaphylaxis.