About Pravastatin Sodium HMG-CoA reductase inhibitor,statins, Antilipemic. Mechanism of Action of Pravastatin Sodium It is an active hydrophilic statin which competitively inhibits the conversion of 3-hydroxy-3-methyl glutaryl coenzyme A (HMG CoA) to mevalonate. The drug exerts it`s action by specific inhibition of enzyme- 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMG CoA reductase) and reduces cholesterol synthesis up to 25% at therapeutic doses. This results in compensatory increase in low density lipoprotein (LDL) receptor expression in liver which ultimately leads to increased receptor mediated uptake and catabolism of intermediate density lipoprotein(IDL) and low density lipoprotein (LDL). It causes lowering of LDL cholesterol and reduces hepatic synthesis of very low density lipoprotein (VLDL) and lowers plasma triglyceride levels. It also increases high density lipoprotein (HDL) levels.