McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 4 7 Lipid-lowering agents

increases uric acid secretion; and may stimulate triglyceride breakdown. It is used for adults with very high triglyceride levels who are not responsive to strict dietary measures and who are at risk for pancreatitis. Peak effects are usually seen within 4 weeks, and the person’s serum lipid levels should be re-evaluated at that time. • Gemfibrozil ( Jezil, Lipazil, Lopid and others) inhibits peripheral breakdown of lipids, reduces production of triglycerides and LDLs and increases HDL concentrations. It is associated with GI and muscle discomfort. This drug should not be combined with statins. There is an increased risk of rhabdomyolysis from 3 weeks to several months after therapy if this combination is used. If this combination cannot be avoided, the individual should be monitored very closely. , known as nicotinic acid (generic), inhibits the release of free fatty acids from adipose tissue, increases the rate of triglyceride removal from plasma, and generally reduces LDL and triglyceride levels and increases HDL levels. It may also decrease the levels of apoproteins needed to form chylomicrons. The initial effect on lipid levels is usually seen within 5 to 7 days, with the maximum effect occurring in 3 to 5 weeks. Nicotinic acid is associated with intense cutaneous flushing, nausea and abdominal pain, making its use somewhat limited. It also increases serum levels of uric acid and may predispose people to the development of gout. Nicotinic acid is often combined with bile acid sequestrants for increased effect. It is given at bedtime to make maximum use of night time cholesterol synthesis, and it must be given 4 to 6 hours after the bile seques- trant to ensure absorption. Peroxisome proliferator receptor alpha activator In 2009, the US Food and Drug Administration (FDA) approved the first drug in a new class of drugs called peroxisome proliferator receptor alpha activators. Fenofibric acid ( Trilipix ) is the first drug in this class. This drug is not yet available in New Zealand and Aus- tralia. It works to activate a specific hepatic receptor that results in increased breakdown of lipids, elimina- tion of triglyceride-rich particles from the plasma, and reduction in the production of an enzyme that natur­ ally inhibits lipid breakdown. The result is seen as a decrease in triglyceride levels, changes in LDL produc- tion that makes them more easily broken down in the body, and an increase in HDL levels. Fenofibric acid is used in combination with a statin to reduce triglycer- ide levels and increase HDL levels in people with mixed lipid disorders; as monotherapy to decrease triglyceride levels in people with severe hypertriglyceridaemia; and as monotherapy to reduce LDL, total cholesterol and Vitamin B Vitamin B 3

■■ The cholesterol absorption inhibitor ezetimibe works in the brush border of the small intestine to prevent the absorption of dietary cholesterol, which leads to increased clearance of cholesterol by the liver and a resultant fall in serum cholesterol. ■■ Change in diet and increased exercise are very important parts of the overall treatment of a person receiving a cholesterol absorption inhibitor. O ther lipid - lowering agents Other drugs that are used to affect lipid levels do not fall into any of the classes discussed previously. They are approved for use in combination with changes in diet and exercise. They include the fibrates (derivatives of fibric acid), the vitamin niacin and the peroxisome pro- liferator receptor alpha activator, fenofibric acid. Fibrates The fibrates stimulate the breakdown of lipoproteins from the tissues and their removal from the plasma. They lead to a decrease in lipoprotein and triglyceride synthe- sis and secretion. The fibrates are absorbed from the GI tract and are metabolised in the liver and excreted in urine. Fibrates in use today include the following agents: • Fenofibrate ( Lipidil ) inhibits triglyceride synthesis in the liver, resulting in reduction of LDL levels; ■ ■ Provide thorough teaching, including the name of the drug, dosage prescribed and schedule for administration; measures to avoid adverse effects, warning signs of problems, and the need for follow-up laboratory testing to monitor cholesterol and lipid levels; dietary and lifestyle changes for reducing the risk of CAD and increasing the effectiveness of drug therapy; and monitoring and evaluation to enhance knowledge about drug therapy and to promote compliance. Evaluation ■ ■ Monitor response to the drug (lowering of serum cholesterol and LDL levels, lowering of sitosterol and campesterol levels). ■ ■ Monitor for adverse effects (headache, dizziness, GI pain, muscle aches and pains, URI). ■ ■ Monitor the effectiveness of comfort measures and compliance with the regimen. ■ ■ Evaluate the effectiveness of the teaching plan (person can name drug, dosage, adverse effects to watch for and specific measures to avoid them; individual understands the importance of continued follow-up). KEY POINTS