Dr. John D. Nelson's challenge, and his concern about the use of ampicillin in streptococcal and other sore throats, directs attention to the importance of selecting the proper antibiotic for those conditions. We said specifically in our paper that ampicillin was "not considered the drug of choice in streptococcal pharyngitis." We reached that conclusion because of the higher incidence of delayed maculopapular rashes and the higher cost. In our study, and in a previous one by Breese et al1 using similar methods, there were no significant differences in failure rates between ampicillin and penicillins V and G. Ampicillin is not indicated in other sore throats because Hemophilus influenzae, against which it is the drug of choice, characteristically produces infection in other parts of the respiratory tract.
Ampicillin was included in the first of two consecutive studies because cephalexin and ampicillin have similar broad antibacterial action against potentially pathogenic bacteria