What is the adult intramuscular dose of epinephrine for severe anaphylaxis accompanied by stridor?

The adult intramuscular dose of epinephrine for severe anaphylaxis is commonly established at 0.3 mg to 0.5 mg of epinephrine in a 1:1,000 dilution. This dosage is crucial for managing severe allergic reactions, particularly when symptoms such as stridor—a high-pitched wheezing sound indicating airway constriction—are present.

Epinephrine acts primarily as a bronchodilator; it relaxes the muscles in the airways and improves breathing by reducing airway swelling. In cases of severe anaphylaxis, timely administration of epinephrine can be life-saving, as it counteracts the effects of histamine release in the body, promoting vasoconstriction and restoring blood pressure.

The choice of 0.3 mg at a 1:1,000 dilution balances efficacy and safety, as it is an appropriate starting dose for adults experiencing anaphylactic shock without overwhelming the cardiovascular system. Dosages exceeding this may increase the risk of adverse effects.

In clinical practice, this dosage is typically administered via intramuscular injection into the mid-anterolateral thigh for rapid absorption. Understanding the correct dosing is critical in emergency situations to ensure the optimal outcome for patients suffering from severe anaphylaxis.