Indication |
For the treatment of hypercholesterolemia. |
Pharmacodynamics |
Simvastatin, the methylated form of lovastatin, is an oral
antilipemic agent which inhibits HMG-CoA reductase. simvastatin is used
in the treatment of primary hypercholesterolemia and is effective in
reducing total and LDL-cholesterol as well as plasma triglycerides and
apolipoprotein B. |
Mechanism of action |
The 6-membered lactone ring of simvastatin is hydrolyzed in vivo
to generate the beta,delta-dihydroxy acid, an active metabolite
structurally similar to HMG-CoA (hydroxymethylglutaryl CoA). Once
hydrolyzed, simvastatin competes with HMG-CoA for HMG-CoA reductase, a
hepatic microsomal enzyme. Interference with the activity of this enzyme
reduces the quantity of mevalonic acid, a precursor of cholesterol. |
Absorption |
Absorption of simvastatin, estimated relative to an intravenous
reference dose, in each of two animal species tested, averaged about 85%
of an oral dose. In animal studies, after oral dosing, simvastatin
achieved substantially higher concentrations in the liver than in
non-target tissues. |
Volume of distribution |
Not Available |
Protein binding |
Both simvastatin and its b-hydroxyacid metabolite are highly bound (approximately 95%) to human plasma proteins. |
Metabolism |
Hepatic, simvastatin is a substrate for CYP3A4. |
Route of elimination |
Following an oral dose of 14C-labeled simvastatin in man, 13% of the dose was excreted in urine and 60% in feces. |
Half life |
3 hours |
Clearance |
Not Available |
Toxicity |
Not Available |