Last week we looked at two popular classes of lipid-lowering medicines: statins and selective cholesterol absorption inhibitors. This week we’ll finish up the lipid-lowering drugs by looking at a few other classes.
Bile acid binding resins: These medicines work by binding to bile acids in the intestine. Because the body needs bile acids, the liver works to convert cholesterol to bile acids; this conversion results in lower levels of cholesterol in the blood. Bile acid binding resins come in different forms. Cholestyramine (brand names Questran, Questran Light, and others) and colestipol (Colestid) are powders that are taken once or twice and day mixed with pulpy fruit or a liquid such as water, juice, or soup. In addition to reducing cholesterol, cholestyramine is also used to treat the itching that can result from liver disease and is sometimes used for treating overdoses of certain drugs. Side effects include constipation, bloating, gas, abdominal pain, and diarrhea. These medicines can affect the absorption of several other drugs, including thyroid hormones, digoxin (used to treat certain heart conditions), and thiazide diuretics (medicines that help rid the body of sodium and water), as well as the absorption of fat-soluble vitamins. Therefore, if you take one of these medicines, you should take it several hours apart from your other medicines.
Colesevelam (WelChol) is another drug that binds to bile acids in the intestine. This medicine comes in tablet form and is taken at mealtimes, usually 1–2 times per day. Side effects include constipation, gas, upset stomach, and heartburn. Colesevelam can decrease the absorption of some medicines, including glyburide (DiaBeta, Micronase, Glynase), thyroid hormones, and certain birth control pills. This medicine can be given along with a statin for additional cholesterol lowering. Interestingly, colesevelam has recently been approved for use as a diabetes drug. It has the ability to lower glucose and HbA1C levels (a measure of blood glucose control over the previous 2–3 months), along with LDL (“bad” cholesterol) levels.
Fibrates: Fibrates are medicines that work primarily to lower triglyceride (blood fat) levels; they may help raise HDL (“good” cholesterol) levels as well. Fibrates reduce the production of triglycerides in the liver. Gemfibrozil (Lopid) and fenofibrate (TriCor, Lofibra) are commonly prescribed fibrates. Because these drugs have little impact on lowering LDL cholesterol, they’re mainly prescribed to people who have high triglycerides and low HDL levels. Fibrates can lower triglycerides by 20% to 50% and raise HDL levels by 10% to 15%. However, fibrates aren’t without side effects: A study in rats given gemfibrozil in high doses found a higher rate of liver tumors. And results of some (but not all) studies using a drug similar to gemfibrozil indicated a possible increased risk of cancer, liver disease, gallstones, and pancreatitis (inflammation of the pancreas). If you take a fibrate or are prescribed one, talk to your health-care provider to make sure it’s the best choice for you. Also, let your health-care provider know immediately if you take a fibrate and you develop an infection or muscle weakness, tenderness, or pain, particularly if accompanied by a fever or unusual fatigue. Fibrates can interact with statins, some diabetes medicines, and blood thinners.
Niacin: Niacin (nicotinic acid) is one of the B vitamins that is needed for converting food into energy. In high doses, niacin can lower LDL and triglycerides and increase HDL. High-dose niacin is sold by prescription, often under names such as Niacinol, Niacor, Niaspan, Slo-Niacin, and Nicotinex. Some common side effects from taking niacin include flushing (which can be reduced by taking aspirin in people taking the extended-release form of the medicine), headache, abdominal pain, and, rarely, liver damage. Niacin can interact with other medicines, including blood thinners, some blood pressure drugs, and multivitamins. It’s possible that niacin might increase blood glucose levels in some people, so if you do take prescription-strength niacin, talk to your provider about this and be sure to closely monitor your blood glucose levels. Niacin is probably underused as an HDL-raising medicine; when taken along with a statin, the benefits might outweigh any possible risks.
Omega-3-acid ethyl esters: A relative newcomer to the arsenal of triglyceride-lowering drugs is Lovaza, a prescription-strength formulation of omega-3 fatty acids. Formerly called Omacor, Lovaza is prescribed for adults with triglyceride levels of 500 mg/dl or higher and is typically taken in four capsules daily. Lovaza can interact with some medicines, including blood thinners. Burping, stomach upset, back pain, and skin rash are some of the possible side effects.