Lack of effect of sucralfate on prednisone bioavailability.

The relative bioavailability of single oral doses of prednisone with and without sucralfate administration was determined in 12 healthy male volunteers. Each subject participated in a randomized three-way cross-over study consisting of the following three phases: treatment A, prednisone given alone; treatment B, 2 days pretreatment with sucralfate with a concomitant dose of sucralfate administered with prednisone; and treatment C, 2 days pretreatment with sucralfate with a sucralfate dose administered 2 h after the oral prednisone dose. Plasma prednisolone concentrations (active moiety of prednisone) were determined by a specific and sensitive high-performance liquid chromatographic assay and unbound prednisolone concentrations were determined by equilibrium dialysis. Bioavailability was assessed by comparing the areas under the plasma prednisolone concentration-time curves as well as peak concentrations, time to peak concentration, elimination rate constant, and half-life. No significant differences were noted in any of the treatment phases for any of the parameters except for the time of peak concentration which was slightly delayed from 1.0 +/- 0.6 to 1.7 +/- 0.9 h when sucralfate was concomitantly administered with the prednisone. Thus, the data from this study indicate that sucralfate does not have a clinically significant effect on the bioavailability of orally administered prednisone. The use of these two drugs in combination does not result in an interaction requiring dosage regimen alteration.