Relative pharmacokinetics of three oral 400 mg ibuprofen dosage forms in healthy volunteers.

The pharmacokinetic properties of two solid form, 400 mg ibuprofen (IP) preparations, a soft gelatin capsule and a film-coated tablet, were compared to those obtained after the administration of liquid prepared from effervescent IP tablets. IP was absorbed rapidly (tmax 0.6-1.9 h). The fastest absorption was observed after the ingestion of the soft gelatin capsule; liquid and film-coated tablet produced 12.2-7.8 times longer absorption half-lives, 50-39% lower peak concentrations of IP in serum and 3.5-3.2 times higher tmax values. Bioavailabilities were close to similar after all products. All products were tolerated without side effects in this single-dose, crossover study on 14 healthy volunteers. The results of this study support the earlier findings that after oral administration, IP is absorbed equally well from solid formulations as from liquid form. Liquid formulations of IP often deliver slower absorption than expected probably due to incomplete dissolution of the active principle. This may have therapeutic significance, and it should be taken into account when studies on the relative bioavailability of IP from pharmaceutical drug products are planned.