Medications for Heart Disease Medications are available to improve blood ﬂow and to minimize symptoms associated with coronary artery disease. The following four types of drugs are frequently used for treating heart disease:
• Beta-blockers interfere with the effects of epinephrinelike hormones in the body that normally increase heart rate and blood pressure. Beta-blockers reduce the resting heart rate. During exercise they limit the increase in heart rate, decreasing the body’s demand for oxygen. Beta-blockers lower the risk of heart attacks and sudden death for people with coronary artery disease. Beta-blockers are estimated to reduce the risk of cardiac death by about 25 percent when taken by people who have had a heart attack. The more serious the heart attack, the more beneﬁt these drugs provide. Possible side effects include slow heartbeat, fatigue, and erectile dysfunction. Some examples of beta-blockers are atenolol, metoprolol, and propranolol.
• Nitrate drugs such as nitroglycerin dilate (widen) the blood vessels, improv- ing blood ﬂow. Both short-acting and long-acting nitrates are available. A small tablet of nitroglycerin placed under the tongue usually relieves an episode of angina in 1 to 3 minutes. The effects of this short-acting nitrate drug last about 30 minutes. People with chronic stable angina are advised to carry nitroglycerin with them at all times. Some people learn through experi- ence to take nitroglycerin just before reaching the level of exertion they know can induce their angina.
Long-acting nitrate drugs are taken one to four times daily. They are avail- able as skin patches or as a paste, which is absorbed through the skin over many hours. Over time, long-acting nitrates lose their ability to provide relief. Most doctors recommend that people try going 8- to 12-hour periods without taking the drug, to help maintain its effectiveness. Possible side effects include headache, ﬂushing of the skin, and dizziness.
• Calcium channel blockers prevent blood vessels from constricting and inter- fering with blood ﬂow. These drugs are also used to treat certain types of arrhythmias because they can slow the heart rate. Possible side effects include headache, ﬂushing of the skin, and dizziness. Some examples of calcium channel blockers are amlodipine, diltiazem, and verapamil.
• Anticlotting drugs such as aspirin are helpful. Platelets are cell fragments cir- culating in the blood that are necessary for clot formation during a bleeding episode or when blood vessels are injured. But when platelets collect on the surface of a plaque on an artery wall, the resulting clot formation (thrombosis) can narrow or block the artery and cause a heart attack. Aspirin binds to
platelets and keeps them from clumping on blood vessel walls, reducing the risk of death from a blocked coronary artery. Regular aspirin use can reduce the risk of death and the risk of a second heart attack by 15 to 30 percent. Peo- ple with a sensitivity to aspirin may take prescription medications that help prevent blood clots, such as dipyridamole and ticlopidine, as a substitute.
If you have heart disease and your cholesterol levels are high, your doctor may recommend that you take cholesterol-lowering medication. Different cholesterol-lowering drugs work in different ways. For example, some drugs decrease blood levels of LDL (“bad”) cholesterol, while others increase levels of HDL (“good”) cholesterol. Still others work by lowering triglyceride (another type of fat) levels in your blood. Your doctor will prescribe a particular medica- tion for you, depending on your individual needs. You may need to take this medication for the rest of your life. Cholesterol-lowering medications include the following:
• Bile acid-binding resins prevent absorption of cholesterol into the blood and stimulate the liver to remove cholesterol from the bloodstream. Possible side effects include bloating, cramping, and diarrhea. Examples of bile acid- binding resins include cholestyramine and colestipol.
• Fibrates (also called ﬁbric acid derivatives) decrease blood levels of triglyc- erides. These drugs also can decrease LDL cholesterol and moderately increase HDL cholesterol levels. People who take ﬁbrates have a slightly increased risk of developing gallstones (see page 276) and gallbladder dis- ease. Examples of ﬁbrates include gemﬁbrozil and fenoﬁbrate.
• HMG CoA reductase inhibitors (also called statin drugs) block the action of an enzyme (HMG CoA reductase) in the liver, thereby signiﬁcantly decreas- ing production of cholesterol in the liver. Possible side effects include occa- sional muscle aches and nausea. Very rarely, liver damage may occur. Examples of statin drugs include atorvastatin and simvastatin.
• Niacin (nicotinic acid) is a vitamin that decreases production of LDL choles- terol in the liver. Depending on the dosage, it also can increase HDL choles- terol levels. Possible side effects include bloating, cramping, and diarrhea. Very rarely, niacin may damage the liver. A variety of nonprescription ver- sions of niacin are available over-the-counter.
• Probucol decreases blood levels of LDL cholesterol but also can decrease blood levels of HDL cholesterol. Diarrhea is the most common side effect of this medication.
You will need to watch for possible side effects while taking certain choles- terol-lowering medications and report them to your physician. Your doctor may ask you to try to live with some side effects for a few weeks to see if your body adjusts to it. Also, your doctor will carefully monitor your cholesterol levels and liver function regularly through blood tests.