The Effect of Sucralfate Pretreatment on the Pharmacokinetics of Ciprofloxacin

Based on the results of our study of norfloxacin‐sucralfate coadministration, we suspected that sucralfate would interact also with ciprofloxacin if the drugs were administered concurrently. Therefore, we decided to give a 1‐g dose of sucralfate at 6 and 2 hours before a single 750‐mg dose of ciprofloxacin and evaluate its effect on the bioavailability of ciprofloxacin. Twelve healthy, male volunteers received ciprofloxacin alone and with sucralfate pretreatment in a randomized, balanced, crossover design. Blood and urine samples were collected over 24 hours after ciprofloxacin administration, and drug concentrations were assayed by high‐performance liquid chromatography. When sucralfate was given at 6 and 2 hours before ciprofloxacin, an average 30% decrease in ciprofloxacin's bioavailability was noted (p < 0.05). Four of the 12 subjects, however, had decreases in the agent's area under the curve of more than 50% with sucralfate pretreatment. The results of this study suggest that ciprofloxacin and sucralfate should not be administered concurrently until a dosing interval is found that will avoid this potential interaction. 1989 Pharmacotherapy Publications Inc.