HPLC Determination of Loratadine in Human Plasma with UV Detection and Pharmacokinetics of Loratadine Following Oral Administration of Tablet Formulation in Human

A validated UV determination of loratadine in human plasma was developed and the pharmacokinetic profiles of single dose of loratadine were determined in 8 healthy volunteers. Human serum samples (1.0 mL) spiked with known concentration of loratadine and 50 ng diazepam as an internal standard were alkalinized with 500 ${\mu}\ell$ ${\mu}\ell$ of 10% $Na_{2}CO_{3}$ and extracted with 7 mL of mixture of isopentane and hexane (2 : 1. v/v) for 5 min. Extracts were centrifuged and 6 mL of organic layer was back-extracted with 150 ${\mu}\ell$ of 12.5% $Na_{2}PO_{4}$ for 1 min. (omitted)