An allergy is when your immune system reacts to a foreign substance, called an allergen. This reaction causes specific clinical symptoms. The allergen could be something you eat, inhale into your lungs, inject into your body, or touch. • An allergic reaction can cause coughing, sneezing, hives, rashes, itchy eyes, a. Allergy: A hypersensitivity reaction mediated via the immune system involving mast cell degranulation and/or inflammatory cell activation in response to an allergenic stimulus. Allergens are generally either proteins or drugs and the reactions are usually reproducible. Anaphylaxis is an acute and potentially lethal multisystem allergic reaction. Intramuscular Epinephrine 1:1,000 is the most effective treatment for Anaphylaxis. Cardiac Epinephrine 1: 10,000 should only be administered to prevent pending arrest refractory to Epi 1:1,000 IM administration. Patients who receive epinephrine should receive ALS consult. An allergic reaction can cause coughing, sneezing, hives, rashes, itchy eyes, a runny nose, swelling, and a scratchy throat. In severe cases, it can cause low blood pressure, breathing trouble, asthma attacks, and even death if not treated promptly and appropriately. There is no cure for allergies. In cases of true penicillin allergy, the source of the reaction is thought to be due to formation of antibodies against metabolites of the penicillin molecule, specifically the R1 side chains of the beta-lactam ring, and not the penicillin molecule or the presence of the beta-lactam ring. • Shortness of breath In extreme pet allergy cases, a severe reaction can occur, known as anaphylaxis, in which the allergic individual may experience itching, hives, swelling, respiratory distress, shock, and even death. Some chemotherapy/biotherapy agents have a need to avoid corticosteroids. Corticosteroids should still be given in cases of severe allergic reactions. Administer epinephrine IM into the antero-lateral mid-third portion of the thigh is preferred.