Localization of drug release sites from an oral sustained-release formulation of 5-ASA (Pentasa) in the gastrointestinal tract using gamma scintigraphy.
Release of 5-ASA from a sustained release formulation (Pentasa, Ferring A/S, Copenhagen, Denmark) was monitored with plasma sampling for up to 24 hours in nine volunteers under both fasted and fed conditions. Drug absorption was correlated with location of the sustained-release microgranules in the gastrointestinal tract by gamma scintigraphy. Disintegration of the labeled tablet preparation occurred in the stomach within 20 minutes and acetylated 5-ASA was detectable in the plasma less than 60 minutes after ingestion. No significant differences were detected in either transit times through the small intestine, peak plasma acetylated 5-ASA concentration or lag time to absorption between fasted and fed individuals. Peak plasma concentration of acetylated 5-ASA usually occurred when the microgranules were present in the small intestine or ascending colon. The pharmacoscintigraphic study confirmed that 5-ASA release from the formulation occurred throughout the gastrointestinal tract, and that food effects on the in vivo behavior of the preparation were minimal.
Hardy
J G
JG
Pharmaceutical Profiles Limited, Nottingham, United Kingdom.
Harvey
W J
WJ
Sparrow
R A
RA
Marshall
G B
GB
Steed
K P
KP
Macarios
M
M
Wilding
I R
IR
D000284:Administration, Oral; D000328:Adult; D000636:Aminosalicylic Acids / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations; D004064:Digestive System / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D019804:Mesalamine; D011877:Radionuclide Imaging; D013270:Stomach / Q000502:physiology; D013997:Time Factors
D000636:Aminosalicylic Acids; D003692:Delayed-Action Preparations; D019804:Mesalamine