Further to some recent messages that dealt with the dosing
regime for Comtan (once a day v. with every dose of
Sinemet), consider the following:
"The plasma elimination half-life of [entacapone] is 1.5 to
3.5 hours." -- Statement quoted from RIVEST J et al. COMT
inhibitors in Parkinson’s disease. Can J Neurol Sci 1999;
Suppl 2, Aug 1999: S34-S38 -- apparently based on NUTT JG et
al. in Neurology 1994; 44:913-919.
Similar information comes from KERANEN T et al [in Eur J
Clin Pharmacol 1994;46(2):151-7], as follows:
"... an open study in 12 healthy young male volunteers ...
Entacapone was rapidly eliminated by metabolism with a
half-life of 0.27-0.30 h after oral doses of 5 to 50 mg.
After doses from 100 to 800 mg the disposition was best
described by two phases with a t1/2 alpha of 0.27-0.37 h and
t1/2 beta of 1.59-3.44 h."
To me this suggests that, in general, a person taking Comtan
once daily would have the benefit of the drug for part - but
not all - of the day.
