Pharmacokinetic Properties of Tramadol Sustained release capsules - 2nd Communication: Investigation of relative bioavailability and food interaction

In an open, randomized four-period crossover study in 24 healthy male volun teers a newly developed tramadol (CAS 27203-92-5) sustained release capsule with and without concomitant food intake and an instant release formulatio n were administered. Additionally, a sustained release tablet was applied a s further reference substance. Statistical analysis of AUC(0-infinity) and C-max after logarithmic transformation yielded bioequivalence of tramadol s ustained release capsules with and without concomitant food intake. Therefo re, lack of food interaction could be concluded. The investigation also sho wed an only slightly diminished bioavailability of the tramadol sustained r elease capsules compared to the instant release formulation. Furthermore, t he sustained release capsules investigated showed enhanced retardation at a lmost identical bioavailability compared with the sustained release competi tor drug.