What is the first-line treatment for anaphylaxis?

The first-line treatment for anaphylaxis is epinephrine. This rapid-acting, adrenergic agonist works by stimulating alpha and beta-adrenergic receptors, leading to several critical responses necessary for managing anaphylaxis. Activation of alpha-1 receptors causes vasoconstriction, which helps to counteract hypotension and prevent shock. Stimulation of beta-1 receptors enhances cardiac output, while beta-2 receptor activation results in bronchodilation, alleviating respiratory distress caused by bronchospasm.

Epinephrine is typically administered intramuscularly in the mid-anterolateral thigh for optimal absorption and is critical for stabilizing the patient's condition during an anaphylactic reaction. It is important to provide this treatment as soon as anaphylaxis is suspected, as delay can lead to severe complications or death.

Other treatments, such as antihistamines and corticosteroids, are not effective as the first-line response for anaphylaxis. Antihistamines can help alleviate itching and hives but do not address the life-threatening components of anaphylaxis, such as airway obstruction or circulatory collapse. Corticosteroids may help reduce the duration of symptoms and potentially prevent a biphasic reaction, but they are not immediate rescue