Persons with a history of severe adverse cutaneous reaction (e.g.,Stevens-Johnson syndrome or toxic epidermal necrolysis) and other severenon–IgE-mediated reactions (e.g., interstitial nephritis or hemolyticanemia) are not candidates for penicillin skin testing or challenge.Penicillin and any other ß-lactam antibiotics should be avoidedindefinitely among these patients, who should be referred to an allergycenter for further evaluation. Here, IGHE is linked to Stevens-Johnson syndrome.