Long-Term Treatment for Angina
Nitrates (nitroglycerin) are the most commonly prescribed medication for treating angina. They are used to relieve chest pain and prevent the onset of angina when physical or emotional stress is anticipated. They dilate (open up) the coronary arteries and veins, which may increase blood flow to the heart, particularly the area receiving an insufficient blood supply.
Nitrates usually are administered as a small pill placed under the tongue, where it quickly dissolves and is absorbed into the bloodstream. Isosorbide dinitrate (Isordil) is usually taken 3 times a day; isosorbide mononitrate (Ismo, Imdur) is taken either twice a day or once daily.
The most common side effects of nitrates are headache, dizziness and flushing. In most cases, the headaches are not severe and occur less frequently or resolve over time. If headache pain is severe, patients can talk to their doctor about reducing the dosage.
Because tolerance to nitrates can develop quickly, combination therapy of a nitrate and a beta blocker or calcium channel blocker is commonly prescribed.
Beta blockers slow the rate at which the heart beats and weaken the contractions of the heart's chambers. This reduces strain on the heart and its need for oxygen.
Beta blockers commonly used include atenolol (Tenormin), metoprolol (Lopressor, Toprol XL), nadolol (Corgard), and propranolol (Inderal). Most of these medications are taken once or twice daily.
Side effects (e.g., fatigue, dizziness) usually are mild and transient. The primary risk is reduced ability of heart muscle to contract and pump blood to the lungs for re-oxygenation (cardiac depression).
Calcium channel blockers relax coronary arteries and veins, which increases blood flow to the heart. This allows the heart to pump blood more easily and decreases strain on the heart. Calcium channel blockers used to treat angina include nifedipine (Adalat), diltiazem (Cardizem), verapamil (Calan, Covera, Isoptin, Verelan).
Side effects include headaches, flushing, dizziness, and swelling (edema). Constipation has been associated with verapamil.
Warfarin (Coumadin) is an anticoagulant that is prescribed for patients who have a history of or are at risk for formation of blood clots (thrombosis).
Cholesterol-reduction therapy reduces the level of "bad" (LDL) cholesterol in the blood using medications called statins: atorvastatin (Lipitor), cerivastatin (Baycol), fluvastatin (Lescol), lovastatin (Mevacor), pravastatin (Pravachol), and simvastatin (Zocor).
Side effects are rare and may include muscle pain and inflammation.
Aspirin Therapy & Other Medications
Long-term treatment for angina sometimes involves aspirin therapy. Aspirin makes platelets less "sticky," decreasing the chances of blood clot formation. Dosage recommendations vary by gender and age.
Studies have shown that some patients are resistant to the effects of aspirin therapy. Regular blood tests may be performed to monitor the patient's response; the results of these tests can be used to adjust the aspirin dosage or change the medication.
Clopidogrel (Plavix), which is slightly more potent than aspirin, also helps prevent blood clots and is considered a longer-term alternative to aspirin therapy for stable angina. Clopidogrel is usually taken in a dose of one 75 mg tablet daily for unstable angina, and it may be prescribed along with aspirin.
Ranolazine extended-release tablets (Ranexa) also may be used to treat chronic angina. This medication, which can be used alone or with other angina treatments (e.g., aspirin therapy, nitrates, beta blockers, calcium channel blockers), is taken twice daily to reduce the risk for angina episodes. Ranexa should not be used in patients with serious liver problems and should be used with caution in patients with a personal or family history of a heart rhythm disorder. The most common side effects include dizziness, headache, constipation and nausea.
There are some differences in the treatment of stable and unstable angina, and it's important that patients speak to their doctors about what type they have and the recommended treatment regimen for their particular cases.