Abstract

In vivo absorption of theophylline and salicylic acid from the rat small intestine was studied by a closed segment technique. The drugs were administered at 1 and 4 mM in dissolved form, both in the presence and absence of phlorizin (0.01 mM). Drug concentrations were measured by high-pressure liquid chromatography. Phlorizin inhibited the absorption of theophylline (pKa = 8.6) at 4 mM but not at 1 mM. In contrast, the absorption of salicylic acid (pKa = 3) both at 1 and 4 mM was unaffected by phlorizin. This suggests that an active transport system, sensitive to phlorizin, is involved in the rat intestinal absorption of theophylline, but not in that of salicylic acid. Apart from differences in drug structure, differences in the degree of ionization may influence the access of acidic drugs to this transport system.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.