Drug therapy
Hyperlipidemias refer to the elevation of cholesterol and/or triglycerides in your blood. In some individuals, only the cholesterol or triglycerides are elevated, in others, both are elevated. Hence hyperlipidemia is used as a term to encompass all elevations of either cholesterol or triglycerides or both.
Drugs for hypercholesterolemia
Hypercholesterolemia refers to the elevation of cholesterol in your blood and is associated with the increase in your LDL which carries most of your cholesterol. Treatment for elevated cholesterol is recommended for any adult patient when your LDL cholesterol level remains greater than 4.9 mmol/L (190 mg/dL) or greater than 4.1 mmol/L (160 mg/dL) in the presence of two or more risk factors as mentioned in the preceding after a sufficient trial of at least 3 months of diet therapy alone. If there are clinical indications that you have been suffering from IHD, drug therapy will be started if your LDL cholesterol level is 3.4 mmol/L (130 mg/dL) or greater.
There are three groups of drugs used to lower your LDL cholesterol. These are:
-bile acid-binding resins
-nicotinic acid
-HMG-CoA reductase inhibitors.
The resins act by enhancing sterol excretion and indirectly increasing LDL receptor-mediated catabolism of circulating LDL. These drugs have been proven by clinical trials to be safe and effective; thus, they can be used for children who have been suffering from familial hypercholesterolemia, and for primary prevention of IHD in young adults. Nicotinic acid has been found to reduce the recurrence of IHD. Based on angiographic studies, regression of IHD has been noted. It uniquely lowers LDL and VLDL levels while raising the HDL, which is considered as the good cholesterol. It is the least expensive drug, and its side effects could be minimized by gradually increasing its dosage. By blocking the rate-limiting step in cholesterol synthesis, the HMG-CoA reductase inhibitors (vastatins) enhance LDL receptor-mediated catabolism of LDL and are very effective in lowering LDL cholesterol levels. Side effects are minimal, and these drugs have been associated with regression of IHD in angiographic trials. Long-term efficacy and safety are being studied.
Drugs for hypertriglyceridemia
Hypertriglyceridemia refers to the elevation of triglyceride (TG) in your blood. If the level of your TG in the blood is greater than 3.4 mmol/L (300 mg/dL) after diet intervention, a fabric acid derivative or nicotinic acid may be tried. Fibrates seem to decrease VLDL synthesis and enhance lipoprotein lipase-mediated catabolism of VLDL, thereby lowering TG and reciprocally raising HDL cholesterol levels.
Drugs for co-existing hypercholesterolemia and hypertriglyceridemia
If cholesterol and triglycerides are simultaneously elevated, then combination therapy may be resorted to. Resin and nicotinic acid may be used to correct the abnormalities.