Adrenal corticosteroids exert a strong suppressive influence on the basic inflammatory response that leads to tissue swelling. The corticosteroid effect is nonspecific. In upper airway obstruction caused by edema from infection, allergy, or trauma, corticosteroids will exert some degree of suppressive effect. The steroid effect is local and directly proportional to the concentration of steroids in the inflamed tissue. In upper airway obstruction steroids should be delivered to the inflamed tissue in high concentration with the least delay. Dexamethasone and methylprednisolone produce high blood levels within 15 to 30 minutes of intramuscular injection. Recommended initial doses for acute airway obstruction are dexamethasone, to mg/kg, or methylprednisolone, 5 to 7 mg/kg. The risk of harm from steroid therapy of 24 hours or less is negligible.
Epinephrine is a direct-acting sympathomimetic agent with various properties that help to reverse the pathophysiological effects of anaphylaxis. The alpha-adrenergic actions of epinephrine work to increase peripheral vascular resistance and reverse peripheral vasodilation while also decreasing angioedema and urticaria. The beta-1 adrenergic effects have positive chronotropic and inotropic effects on the heart, while the beta-2 adrenergic effects cause bronchodilation and reduction of inflammatory mediator release from mast cells and basophils  . In combination, these effects help to reverse the anaphylactic process and, in turn, improve the cutaneous, respiratory and cardiovascular effects of the condition.
In hereditary angioedema , specific stimuli that have previously led to attacks may need to be avoided in the future. It does not respond to antihistamines, corticosteroids, or epinephrine. Acute treatment consists of C1-INH (C1-esterase inhibitor) concentrate from donor blood, which must be administered intravenously. In an emergency, fresh frozen blood plasma, which also contains C1-INH, can also be used. However, in most European countries, C1-INH concentrate is only available to patients who are participating in special programmes. [ citation needed ] The medications ecallantide and icatibant may be used to treat attacks.  In 2017 these medications cost between 5,700 and 14,000 US$ per dose in the United States, prices that tripled in two years.  [ medical citation needed ]