Controlled release levodopa/carbidopa 25/100 (Sinemet CR 25/100): pharmacokinetics and clinical efficacy in untreated parkinsonian patients.
The pharmacokinetics of the clinically determined optimal dose of controlled release levodopa/carbidopa 25/100 (Sinemet CR 25/100) after 12 weeks of therapy was studied in nine parkinsonian patients without prior exposure to levodopa. The pharmacokinetics of single oral doses of controlled release levodopa/carbidopa 25/100 and 50/200 were also compared. As predicted from the plasma half-life (1.7 +/- 0.3 h) and confirmed by morning trough levels, levodopa did not accumulate when controlled released levodopa/carbidopa 25/100 was administered twice daily. The absorption and bioavailability of CR 25/100 are minimally greater than CR 50/200. Controlled released levodopa/carbidopa 25/100 levodopa plasma levels peak slightly faster than controlled release levodopa/carbidopa 50/200.
Hammerstad
J P
JP
Department of Neurology, Oregon Health Sciences University, Portland 97201, USA.
Woodward
W R
WR
Nutt
J G
JG
Gancher
S T
ST
Block
G A
GA
Cyhan
G
G
D000042:Absorption; D000978:Antiparkinson Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D001682:Biological Availability; D002230:Carbidopa / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology*; D003692:Delayed-Action Preparations; D004338:Drug Combinations; D006801:Humans; D007980:Levodopa / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology*; D010300:Parkinson Disease / Q000188:drug therapy* / Q000378:metabolism*
D000978:Antiparkinson Agents; D003692:Delayed-Action Preparations; D004338:Drug Combinations; C009265:carbidopa, levodopa drug combination; D007980:Levodopa; D002230:Carbidopa