Mesalazine release from a pH dependent formulation: effects of omeprazole and lactulose co-administration.
OBJECTIVE
Delayed-release formulations of mesalazine often rely on the gastrointestinal luminal pH profile to deliver 5-aminosalicylic acid (5ASA) to the colon. The aim of this study was to examine the influence of luminal pH on mesalazine release.


METHODS
We studied the effect of co-administration of omeprazole and lactulose on the steady-state pharmacokinetics of Eudragit S-coated mesalazine in healthy volunteers.


RESULTS
No significant changes in urinary or faecal levels of 5ASA or its main metabolite, N-acetyl 5ASA, were apparent.


CONCLUSIONS
This study suggests that co-administration of omeprazole and lactulose does not impair the release of delayed-release mesalazine.
Department of Gastroenterology, Northern General Hospital, Sheffield.
F N
FN
Hussain
R A
RA
Ajjan
M
M
Moustafa
N W
NW
Weir
S A
SA
Riley
D000293:Adolescent; D000328:Adult; D000897:Anti-Ulcer Agents / Q000494:pharmacology*; D003692:Delayed-Action Preparations; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005765:Gastrointestinal Agents / Q000494:pharmacology*; D006801:Humans; D007792:Lactulose / Q000494:pharmacology*; D019804:Mesalamine / Q000378:metabolism* / Q000493:pharmacokinetics; D008875:Middle Aged; D009853:Omeprazole / Q000494:pharmacology*; D054328:Proton Pump Inhibitors
D000897:Anti-Ulcer Agents; D003692:Delayed-Action Preparations; D004791:Enzyme Inhibitors; D005765:Gastrointestinal Agents; D054328:Proton Pump Inhibitors; D007792:Lactulose; D019804:Mesalamine; D009853:Omeprazole