Lubiprostone - Pharmacokinetics

Pharmacokinetics

Unlike many laxative products, Lubiprostone does not show signs of tolerance, dependency, or altered serum electrolyte concentration. There was no rebound effect following withdrawal of treatment, but a gradual return to pre-treatment bowel movement frequency should be expected.

Minimal distribution of the drug occurs beyond the immediate gastrointestinal tissues. Lubiprostone is rapidly metabolized by reduction/oxidation, mediated by carbonyl reductase. There is no metabolic involvement of the hepatic cytochrome P450 system. The measurable metabolite, M3, exists in very low levels in plasma and makes up less than 10% of the total administered dose.

Data indicate that metabolism occurs locally in the stomach and jejunum.