Comparative bioavailability of a new formulation of fluoxetine drops.

Fluoxetine drops and marketed fluoxetine capsules had quite the same Cmax (50.25 +/- 4.43 vs 47.55 +/- 5.29 ng/ml), but significantly different AUC0-t (717.27 +/- 71.29 vs 644.91 +/- 78.91 ng/ml/h). Furthermore the drops were characterised by a very early Tmax (4.61 +/- 0.85 hours) with a highly significant difference in comparison to the capsules reference compound (6.72 +/- 1.23 hours). After log transformation 90% C.I. for Cmax, AUC 0-t and AUC0-. were 1.05, 1.11, 0.82 respectively. The two products, therefore, cannot be considered bioequivalent. Our results demonstrate that fluoxetine drops and capsules significantly differ for their pharmacokinetics, with an earlier Tmax and a higher AUC0-t after the administration of the drops preparation.