Acute heart failure in young people may have other etiologies than myocarditis. We report about a twenty-year-old female developing acute heart failure following an anaphylactic reaction after a Prick test. Initially her left ventricular ejection fraction was severely compromised on echocardiography but normalized quickly. We postulated an anaphylactic shock-associated cardiomyopathy due to the close temporal association to an anaphylactic reaction, the presence of hypereosinophilia, and the absence of specific serologic, microbiologic, and immunologic abnormalities. Anaphylactic-associated cardiomyopathy very likely represents a common cause of acute heart failure and should be thought of in young people with known atopy.