Contact dermatitis to semisynthetic penicillins in factory workers

45 workers developed dermatitis after handling semi-synthetic penicillins in a factory. All reacted on patch test, but several agents had to be used. Only 7 reacted to benzyl penicillin. 1/3 reacted to only one allergen, while 2/3 reacted to several. The duration of exposure before symptoms was short, often less than 2 months. 19 had hay fever or asthma, and they developed their symptoms after a shorter exposure time. A survey for airborne antibiotics was performed.