Throat, lip, and tongue swellingTrouble breathingDizzinessHeadacheStomach cramps, nausea, or diarrheaShockLoss of consciousnessAnaphylaxis can be caused by an allergic reaction to a medicine, food, serum, bug venom, allergen extract, or chemical. The most common causes of an anaphylactic reaction are food, insect stings, medicines, and latex. Some