Release of 5-ASA from Pentasa in patients with Crohn's disease of the small intestine.

BACKGROUND

Pentasa is a controlled-release tablet made from semipermeable microspheres and designed to continuously deliver therapeutic quantities of 5-ASA (5-aminosalicylic acid) throughout the gastrointestinal tract. Scintigraphic studies in healthy subjects have documented that 5-ASA release could occur in the small intestine. We tested here the disintegration of Pentasa in the digestive tract of nine patients with Crohn's disease of the small intestine.

MATERIALS

Each patient was given, after breakfast, a 250 mg tablet of Pentasa containing samarium-153 oxide. For 8 h the progression of the isotope in the gastrointestinal tract was followed using gamma camera scintigraphy. Plasma measurement of 5-ASA and acetylated 5-ASA was used to verify the liberation and absorption of 5-ASA.

RESULTS

The Pentasa tablet appeared completely dissolved in the stomach by 117 +/- 18 min. Samarium oxide was first detected in the small intestine 60 +/- 5 min after its ingestion; it reached the colon after 280 +/- 13 min and it was completely absent from the small intestine at 360 +/- 26 min. Plasma concentrations of 5-ASA started to rise after 67 +/- 7 min and were maximal at 222 +/- 25 min.

CONCLUSION

In patients with Crohn's disease of the small intestine, Pentasa microgranules start releasing 5-ASA in the proximal small intestine, acting locally to exert its beneficial effect.