To evaluate the effect of food on bioavailability, clarithromycin and 14‐hydroxy clarithromycin (active metabolite) pharmacokinetics were assessed in 26 healthy adult volunteers after ingestion of a single oral 500‐mg dose of clarithromycin in a fasting state (2 hours before breakfast after an overnight fast) and a nonfasting state (0.5 hours after the start of breakfast). Clarithromycin and 14‐hydroxy metabolite plasma concentrations were measured using a high‐performance liquid chromatographic technique. Food intake immediately before dosing increased the extent of absorption from the 500‐mg tablet formulation by approximately 25%. The mean increase in metabolite area under the plasma concentration‐time curve was approximately 9%. These results suggest that clarithromycin can be taken without regard to timing in relati