Oral, rectal, and vaginal pharmacokinetics of misoprostol.
OBJECTIVE
To compare the pharmacokinetic profiles of orally, rectally, and vaginally administered misoprostol tablets in pregnant women.


METHODS
Women between 7 and 14 completed weeks of gestation were recruited and randomly assigned to be given 400 microg misoprostol orally, rectally, or vaginally 3 hours before surgical termination of pregnancy. Blood samples were obtained at 0, 7.5, 15, 30, 45, 60, 90, 120, and 240 minutes and later analyzed for plasma concentrations of misoprostol free acid (the principle metabolite).


RESULTS
Vaginal misoprostol was present in the circulation longer than oral misoprostol and had a greater area under curve at 240 minutes (P <.001). Rectal misoprostol had a similar pattern but a much lower area under curve at 240 minutes. Oral misoprostol had a significantly greater peak plasma concentration and a shorter duration to maximum concentration than either rectal or vaginal misoprostol (both P <.001).


CONCLUSIONS
Oral misoprostol tablet is also absorbed by the rectal and vaginal routes. Misoprostol administered in early pregnancy has route-dependent pharmacokinetics and is absorbed best when administered vaginally.


METHODS
I
Khan
Rehan-Uddin
RU
Chelsea and Westminster Hospital, London United Kingdom.
El-Refaey
Hazem
H
Sharma
Sunita
S
Sooranna
Dev
D
Stafford
Mike
M
D000282:Administration, Intravaginal; D000284:Administration, Oral; D000285:Administration, Rectal; D000328:Adult; D005260:Female; D006801:Humans; D016595:Misoprostol / Q000008:administration & dosage / Q000493:pharmacokinetics*
D016595:Misoprostol