In-vivo effects of clindamycin on neutrophil function--a preliminary report.

Neutrophil functions were evaluated in six normal subjects who had received 300 mg of clindamycin orally four times each day for two days. The mean serum concentration was 1.0 mg/l at the time of neutrophil collection. Clindamycin increased phagocytosis of a clindamycin-resistant staphylococcus from 0.8 to 1.0 organism per polymorphonuclear leukocyte (P less than 0.05). The proportion of killed intracellular bacteria increased from 23.8% to 29.8%. Zymosan-induced chemiluminescence was reduced from 130 X 10(3) to 86 X 10(3) counts per 0.2 min (P less than 0.05). Chemotaxis was unaffected. These preliminary results demonstrate measurable effects of clindamycin on neutrophil functions in the host; however, further studies are needed in order to confirm the observed changes.