Pharmacokinetics of liposomal levamisole after oral, intramuscular, and subcutaneous administration in sheep

Abstract

This study aimed to determine the pharmacokinetics of free and liposomal levamisole in sheep following single oral (O), intramuscular (IM), and subcutaneous (SC) administrations at a dose of 7.5 mg/kg. The study developed a levamisole liposome and investigated relevant parameters: particle size, zeta potential, polydispersity index, encapsulation efficiency, pH, and morphology. The Bangham method, a thin-film hydration technique, was employed to prepare the liposomal levamisole. Blood samples were collected by jugular venipuncture in heparinized tubes immediately before each free and liposomal levamisole treatment and at 2.5, 5, 10, 15, 30, 60, 90, 120, 240, 360, and 480 min and 12, 16, and 24 h after O, IM, and SC administration. Free and liposomal levamisole plasma concentrations were measured using high-performance liquid chromatography ultraviolet (HPLC-UV). The pharmacokinetic study showed that the O (p: 0.036) and SC (p: 0.047) liposomal levamisole groups had higher maximum concentrations (Cmax) than the free levamisole groups. A comparison of the liposomal administration routes revealed no significant difference in Cmax between IM and SC administration. However, both methods showed better results than O administration. The last observed quantifiable concentration, area to the last experimental point, zero to infinite area, and total body clearance values were found to be better with IM administration than the other two. In conclusion, liposomal levamisole preparation provides plasma concentrations that are therapeutically effective for a longer period than free levamisole, making it more effective and convenient for treatment.