Amoxicillin was used in the treatment of 36 infections in 35 patients with adequate granulocyte counts. The antibiotic was effective against 61% of all infections, against 90% of infections caused by gram-positive organisms, and against 77% of infections caused by Escherichia coli, and Proteus mirabilis. Superinfection with Pseudomonas, Klebsiella, and Proteus vulgaris occurred in 8% of the cases. Transient side effects attributed to amoxicillin were abdominal cramps (I patient) and erythematous skin rash (2 patients). © 1973.