An Overview of Lipid-Lowering Drugs

The long term use of lipid-lowering drugs in the treatment of patients with hyperlipoproteinaemia is aimed at reducing plasma concentrations of known atherogenic lipoproteins with a favourable effect on lipid deposition in the arterial wall. A less common aim is to prevent the adverse sequelae of hyperchylomicronaemia in patients with severe hypertriglyceridaemia. The decision to begin drug therapy should be made only after the exclusion of secondary factors and after an adequate trial of diet has failed to produce acceptable concentrations of plasma lipids and lipoproteins. The bile acid sequestrants (cholestyramine and colestipol), nicotinic acid, fenofibrate and inhibitors of hydroxymethylglutaryl coenzyme A (HMG CoA) reductase (e.g. lovastatin or simvastatin) are the most effective drugs for use in patients with primary hypercholesterolaemia; these agents reduce plasma concentrations of total and LDL-cholesterol by 15 to 45%. For those patients with concurrent hypertriglyceridaemia, nicotinic acid, lovastatin or simvastatin, or fenofibrate are the preferred drugs for initial use; bile acid sequestrants frequently exacerbate hypertriglyceridaemia in these patients. Fibric acid derivatives (e.g. clofibrate, gemfibrozil, bezafibrate or fenofibrate) are all effective in the therapy of patients with type III hyperlipoproteinaemia, as is nicotinic acid and I have found lovastatin to be effective also. Gemfibrozil or nicotinic acid are the most effective agents to use in the treatment of patients with severe hypertriglyceridaemia who are at increased risk of abdominal pain and pancreatitis. Combined therapy with drugs which have different mechanisms of action can be effectively used in the treatment of patients with severe hypercholesterolaemia or combined hyperlipidaemia; for the former group, combinations which use bile acid sequestrants, HMG CoA reductase inhibitors and nicotinic acid are the most effective.