Why was Chiquinha first treated with epinephrine in the emergency room?

Chiquinha experienced a hyperreaction to peanuts. Allergens are those antigens which cause allergic reactions, in this case allergen is peanut butter. Anaphylactic reactions to allergens are most common and occur within minutes after person is re-exposed. During first encounter, IgE antibodies are formed. On re-exposure these antibodies bind on surface of mast cells and basophils. This leads to release of histamine, prostaglandins, kinins and leukotrienes. This leads to vasodilation and some may experience inflammatory response, as did Chiquinha. Symptoms includes swelling, runny nose, and difficulty breathing. In extreme cases can lead to anaphylactic shock (life threatening emergency), and it is generally treated by epinephrine injection which causes airway dilation and heartbeat strengthening. Epinephrine binds to beta-2-adrenergic receptors on bronchiole muscle cells, which causes them to relax and dilate.