In a clinical trial comparing two brands of ampicillin, similar proportions of patients developed dermatologic reactions with each product. This finding, taken in conjunction with epidemiologic data on other brands, suggests that there is no substantial difference with regard to cutaneous eruptions between the various commercially available brands of ampicillin. Current epidemiologic data suggest that the attributable risk for ampicillin rashes with all brands is about 9%. The morphologic characteristics of the ampicillin rashes were similar to those of drug eruptions in general.
Ampicillin RashesCollaborative Study. Arch Dermatol. 1973;107(1):74-76. doi:10.1001/archderm.1973.01620160046013