Routine Use of Penicillin Skin Testing on an Inpatient Service

The routine use of prospective penicillin skin testing on hospitalized patients was evaluated over a six-month period. Patients with clinical indications for the use of penicillin drugs were tested with penicilloyl-poly-L-lysine (PPL) and a mixture of minor penicillin antigens (MDM), regardless of past history of penicillin reactions. Fifty-four patients with reasonable histories of penicillin hypersensitivity but nonreactive skin tests were treated, with only one mild possible reaction occurring within the first three days of therapy; this patient had active systemic lupus erythematosus. Ten of 163 patients without histories of prior penicillin reactions had positive skin tests and were denied penicillin drugs. As compared to a similar study of the same inpatient population in 1964–65, penicillin reactions were markedly less frequent. The routine use of PPL and MDM skin tests by house officers on a busy ward service is practical, safe and useful in predicting penicillin reactions.