Preliminary observations on the absorption of liposome-encapsulated drug by the intestinal lymphatics.

The absorption of liposome-encapsulated drug by the intestinal lymphatics was investigated in Sprague-Dawley rats after quinidine liposomes were given by oral intubation and direct introduction into the duodenum. When compared to an aqueous solution and drug given with empty liposomes, liposome encapsulation retarded the rate of lymphatic quinidine absorption after oral administration and increased the rate after intraduodenal administration. The lipid properties of the liposomes are one possible explanation for these divergent observations. The liposomes had no effect on the extent of lymphatic drug absorption. The results show that substantial work is needed in this area.