Amblyomma americanum mammalian meat and meat products. The allergy manifests as anaphylaxis — a life-threatening allergic reaction characterized by constriction of airways and a drop in blood pressure. This response is triggered by an IgE antibody to the mammalian oligosaccharide galactose-alpha-1,3-galactose (alpha-gal). As well as occurring in non-primate mammals, alpha-gal is also found in cat dander and in the drug cetuximab. Allergic reactions to alpha-gal usually occur 3–6 hours after consuming red meat, unlike allergic reactions to other foods, whose onset following consumption is more or less immediate, making it more difficult to identify what caused the reaction. Skin tests with standard
Allergic transfusion reaction antihistamine and if the symptoms completely disappear and the patient feels well, the transfusion may be restarted. A mild transfusion reaction during infusion usually does not progress to a more severe anaphlyactic reaction after infusion of additional product from the same unit. If the symptoms are more than mild, the transfusion should not be restarted. There is no evidence that antihistamine premedication prevents allergic transfusion reactions, although these drugs can mitigate symptoms once they occur. Allergic transfusion reaction An allergic transfusion reaction is a blood transfusion that results in allergic reaction. It is among the most common transfusion reactions to