Propagation of Error in Ocular Pharmacokinetic Parameters Estimate of Azithromycin in Rabbits

The ocular pharmacokinetic (PK) of azithromycin in rabbit eye tissues was evaluated following single-dose and multiple-dose administrations of azithromycin. Because of destructive sampling, only the average ocular tissue concentration-time curve could be captured and used to estimate the PK parameters failing to obtain their standard deviations. In the present study, formulas were explained in details to estimate the major PK parameter errors in destructive sampling. The PK parameters were obtained by analyzing average ocular tissue concentration-time curve and their standard deviations were calculated using the formula proposed in this paper. A case study was included to elucidate the potential application of the formulas. F-test for equality of variances and independent-samples t-test were carried out between test formulation and reference formulation in PK parameters. Thus, a new and simple method was proposed to compare PK behavior for these studies using destructive sampling, which can be potentially applied into other cases in the future. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:2371-2379, 2013