Erythema multiforme from betalactams with positive cutaneous tests

We report the case of a woman who after taking ampicillin and amoxicillin d eveloped two severe cutaneous reactions with generalized erythema and macul opapular rash, which later turned into blisters with subsequent desquamatio n. She was clinically diagnosed with erythema multiforme syndrome after pos itive delayed cutaneous tests with benzylpenicillin, amoxicillin and ampici llin allowed for a more specific diagnosis. There are very few references t o patients with drug reactions to betalactams who have positive skin prick or intradermal test but show delayed hypersensitivity, as was the case in o ur patient.