Evaluation of dosage forms. IV. Studies on commercial phenylbutazone tablet dosage forms

In order to determine the feasibility of dissolution-dialysis as a suitable technique for in vitro evaluation, studies on commercial phenylbutazone tablets were carried out. Although disintegration time and dissolution parameters did not give a true indication of bioavailability, an excellent correlation was obtained between the dialysis rate constant (K) and various pharmacokinetic parameters obtained from bioavailability studies on human volunteers.