Agranulocytosis during therapy with orally administered cloxacillin

Agranulocytosis developed in a patient with staphylococcal osteomyelitis after 35 days of treatment with orally administered cloxacillin. The patient had fever, prostration, pharyngitis, and profound leukopenia, which subsequently abated upon withdrawal of the drug. Cloxacillin should be included in the growing list of drugs capable of producing leukopenia and agranulocytosis.