Classification of ß-lactam Allergic Reactions
| Type of Reaction | Clinical Manifestations | Usual Onset |
|---|---|---|
| I Immediate (IgE - mediated) occurs upon repeat exposure |
Anaphylaxis - hypotension with exposure, or two of:
|
within 1 hour (anaphylaxis) - up to 72 hours |
| II Cytotoxic (IgG or IgM mediated) |
Hemolytic anemia, agranulocytosis, leukopenia, thrombocytopenia | > 72 hours |
| III Immune Complex | Serum sickness (cefaclor, cefprozil), drug-induced fever, allergic vasculitis, interstitial nephritis | 7-14 days |
| IV T-cell mediated (delayed) |
Contact dermatitis, exfoliative dermatitis, maculopapular or morbilliform drug eruptions | > 72 hours |