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MedicationsDRUGS COMMONLY USED IN CARDIOVASCULAR MEDICINE It is always important to continue any medication started by your physician until having a discussion with your physician about discontinuing that medication. What follows below is a general outline and introduction to many of the drugs used to treat patients with cardiovascular disease. You should discuss any specific questions with your pharmacist or physician. Drugs will be broken down into categories of drugs. While each individual agent in such a category will have specific and unique characteristics, many of the agents in such classes share significant number of characteristics. ANGIOTENSIN CONVERTING ENZYME INHIBITORS The angiotensin converting enzyme inhibitors (ACEI) are a family of drugs which block an enzyme in the body which converts one form of the enzyme angiotensin into another. These drugs are very effective in treating hypertension (high blood pressure), congestive heart failure, or patients who have recently suffered a myocardial infarction (heart attack). These drugs may also be useful in patients with diabetes and certain kidney disorders. The ACE inhibitors have proven to be very effective in patients with high blood pressure and not only improve symptoms in congestive heart failure but also may prolong life. These drugs have been shown to also limit the development of congestive heart failure after a myocardial infarction and they are often used in that setting. There are significant differences within this class and certain drugs within it have unique characteristics. Side effects or adverse effects of these drugs may include skin rash which at times can be quite serious. A dry hacking cough which may necessitate changing to another class of drugs, alteration in kidney function which may sometimes require discontinuation of the drug. Drugs in this class include Accuprilâ (quinapril), Aceonâ (perindopril), Altaceâ (ramipril), Capotenâ (captopril), Lexxelâ (enalapril), Lotensinâ (benazepril), Monoprilâ (fosinopril), Prinivilâ (lisinopril), Vasotecâ (enalapril) and Zestrilâ (lisinopril). ANGIOTENSIN-II RECEPTOR ANTAGONISTS The angiotensin II receptor antagonists are a family of drugs that are relatively new. They work to block the effect of angiotensin II directly at its receptor. These drugs therefore share some similar effects with those of the angiotensin converting enzyme inhibitors, however these drugs are different from that class of drugs and have significant differences in their effects. They have been shown to be very useful in the treatment of hypertension (high blood pressure). Preliminary results of research show that they may be beneficial in congestive heart failure and after myocardial infarction. However, there are limited data on these last two uses and it is not now known with certainty whether or not the A-II blockers will be as effective as ACE inhibitors. A-II inhibitors as a class tend to have fewer side effects than the ACE inhibitors. Drugs within this family include: Avaproâ (irbesartan), Cozaarâ (losartan), Diovanâ (valsartan). ALPHA (a ) BLOCKERS The Alpha Adrenergic blocking agents are generally used in the treatment of hypertension. Some of the drugs in this family have beneficial effects on the treatment of prostate hypertrophy. These drugs can dilate the peripheral arteries, therefore causing a drop in blood pressure. This makes these agents excellent choices for the treatment of high blood pressure. Occasionally, after the first dose of these medications the fall in blood pressure can be significant causing loss of consciousness, therefore the first dose should generally be taken at night just prior to retiring to bed. Common side effects include dizziness, sleepiness, nasal congestion and fatigue or tiredness. Drugs in this category include Carduraâ (doxazosin mesylate), Hytrinâ (terazosin HCl), Minipressâ (prazosin). There are also agents known as central adrenergic blocking agents. These act in the brain to block the constriction of the arteries. These are also used for the treatment of high blood pressure. Their side effects are very similar to the those of the peripheral alpha adrenergic blocking agents. The major drugs in this category include Aldometâ (alpha-methyldopa), Catapresâ (clonidine). There are a group of drugs that have both alpha and beta adrenergic blocking activity. These share characteristics of both the alpha and beta blockers. Drugs in this category include Coregâ (carvedilol), Normodyneâ (labetalol), Trandateâ (labetalol). BETA (b ) BLOCKERS The beta blocking drugs are among the most widely used and important drugs in cardiovascular medicine. These drugs act to block the receptor for adrenalin and like hormones within the body. They have as their major effects slowing the heart rate, decreasing the blood pressure, decreasing the force of contraction and therefore oxygen utilization of the heart muscle. These drugs have been shown by innumerable research studies to have significant beneficial effects in areas as diverse as high blood pressure, angina, patients with acute myocardial infarction, patients after myocardial infarction, patients with congestive heart failure, and patients with cardiac arrhythmia. In many of these medical conditions the beta blockers have been shown to significantly prolong life and improve clinical outcomes. The use of these drugs in many instances will significantly improve both the quality and the length of life. The side effects of beta blockers are not to be ignored. These drugs cause as part of their action slow heart rates and may lower blood pressure. These generally can be well tolerated. They can cause fatigue, weakness, dizziness, tiredness and depression. In most cases these side effects can be well tolerated. Once started, these drugs should generally not be stopped suddenly, and certainly not stopped without consultation with a physician, even if side effects are present. Often when stopped these drugs have to be discontinued slowly, gradually decreasing the dose. There are many members of this family of drugs, several of which include Inderalâ (propanolol), Lopressorâ (metoprolol), Toprolâ (metoprolol), Tenorminâ (atenolol), Zebetaâ (bisoprolol), Blocodrenâ (timolol). CALCIUM ANTAGONISTS (CALCIUM CHANNEL BLOCKERS) The family of calcium antagonists is also one where there are many very potent and useful drugs utilized in cardiovascular medicine. These drugs, much like the beta blockers have a wide variety of uses. Calcium channel antagonists can be used in the treatment of hypertension, angina pectoris, and cardiac arrhythmias. These drugs have a wide variety of actions and there is a large amount of variation in the actions of the drugs within this general family. Drugs such as nifedipine (Procardiaâ , Adalatâ ) are used primarily in hypertension and occasionally in angina. The drugs verapamil (Calanâ , Isoptinâ ) and diltiazem (Cardizemâ , Tiazacâ ) are used for hypertension, angina, as well as cardiac arrhythmias. There are a variety of other drugs within the calcium channel blocking family and new drugs are being developed daily. Side effects from these drugs may include headache, slow heart rate, and swelling of the ankles (edema). CHOLESTEROL LOWERING DRUGS There are many drugs that are utilized to lower cholesterol today. Perhaps the most potent and most commonly used are the drugs in the "statin" family. However, drugs which bind bile acid have been used for many years. Also, drugs which are derivatives of fibric acid are commonly used. The "statin" drugs are drugs which inhibit the liver enzyme HMG-CoA reductase enzyme. There are many drugs in this family, some of which are known by the trade names Mevacorâ , Pravacholâ , Zocorâ , Lescolâ , Baycolâ , and Lipitorâ . The bile acid sequestering drugs are perhaps the oldest in the treatment of high cholesterol. The most commonly used today are Questranâ and Colestidâ . The fibric acid derivative drugs are also used today. These include Atromid-Sâ as well as Lopidâ . The vitamin niacin is also used to lower cholesterol. The most common formulation used today in Niaspanâ . All drugs which lower cholesterol may cause as side effects a variety of gastrointestinal symptoms. This may include constipation, diarrhea, bloating, excess gas, and abdominal distress. Many of these agents may also alter the function of the liver and the liver enzymes. It has been shown in numerous studies that lowering of cholesterol may significant improve the outcome of patients with or at high risk for myocardial infarction and coronary artery disease while it is not clear if drug therapy is superior to dietary therapy, it is clear that dietary therapy alone has a significant positive impact. However, dietary manipulation often leads to small changes in total cholesterol and therefore drug therapy is used in the vast majority of patients with documented coronary artery disease. While drug side effects may occur, it is often possible to find a tolerable regimen which successfully lowers cholesterol to target values. (see Risk Factors) DIURETICS Diuretics or "water pills" are commonly used to help patients with congestive heart failure eliminate excess body water and salt and in the treatment of high blood pressure or hypertension. Among the most potent diuretics are those known as "loop diuretics". These include Lasixâ (furosemide), as well as Bumexâ (bumetanide), and Demadexâ (torsemide). These drugs may be given either orally or intravenously and are generally reserved for the treatment of congestive heart failure. The thiazide diuretics (Hydrochlorothiazide) and others, are often used in the treatment of hypertension as well as mild congestive heart failure. The drug Zaroxolynâ is used to treat resistant congestive heart failure. The potassium diuretic Aldactone has been recently shown to significantly improve the outcome of patients with congestive heart failure. Side effects from diuretics include excess loss of fluid leading to dehydration, excess loss of potassium, which may be life threatening. Diuretics may also cause a variety of other side effects which are much less common. These include significant skin rashes. Whenever taking diuretics, if your physician prescribes potassium supplements it is important to take your potassium and to have your potassium levels in your blood monitored closely. DIGITALIS Digitalis is perhaps one of the oldest drug therapies used for the treatment of both congestive heart failure and cardiac arrhythmia. This derivative of the Foxglove plant has been used for centuries first as an herbal remedy for the treatment of dropsy and rapid cardiac rhythm. The most common preparation used today in North America is digoxin(Lanoxinâ ). This drug has significant potency for the treatment of heart failure as well as atrial fibrillation and supraventricular tachycardia. Careful attention to dosage and if needed drug levels need be given to help ensure that digitalis toxicity (a common side effect) does not occur. Digitalis is helpful in improving and strengthening the contractile function of weakened heart muscle and in controlling rapid heartbeats. Side effects may include visual difficulties as well as cardiac arrhythmias. The later may be at times life threatening. Fortunately, specific antidote (Digibindâ ) is available for treatment of serious digitalis toxicity. ANTICOAGULANTS The anticoagulant warfarin (Coumadinâ ) is the most commonly used in North America. This potent "blood thinner" is very useful in limiting the risk of thrombosis. Coumadinâ is used to help prevent clotting in patients with artifical heart valves, congestive heart failure, and atrial fibrillation. Studies have shown that patients with these conditions treated with Coumadinâ have significantly lower risks of cerebral vascular accidents (stroke). Frequent testing of the therapeutic effects of warfarin (prothrombin time, INR) is required to prevent toxicity. The most common side effect from warfarin therapy is excessive bleeding. This at times may be life threatening. Less commonly, skin reactions may be seen. ANTIPLATELET DRUG THERAPY Antiplatelet therapy is used widely today in the treatment of cardiovascular disease. Blood clotting may be treated with warfarin, however when platelets aggregate and form clots the risk of heart attack and stroke is significant. Aspirin is a relatively potent drug inhibiting the clotting of the platelet. Newer, more potent and perhaps better tolerated drugs currently available include ticlopidine (Ticlidâ ), clopidogrel (Plavixâ ). These drugs are commonly used in patients undergoing coronary artery angioplasty and stenting. It is not uncommon to combine these drugs with aspirin and occasionally with Coumadinâ . In the hospital, intravenous drugs may be given which likewise inhibit platelet clotting. The most widely used today is an antibody derivative known as a ReoProâ . This very potent drug lessens the risk of clotting in the heart artery after angioplasty. The major side effect of the use of these agents is bleeding. This may at times be life threatening. Ticlopidine is used less commonly today because of concern over the potential side effect of altering the function of bone marrow. ANTIARRHYTHMICS The antiarrhythmic family is a group of drugs used to treat irregular heart beats or cardiac arrhythmias. Because of significant side effects of these drugs, many of them have fallen out of favor in recent years. This has also been combined with recent data which throws into question the benefit of therapy with many of these drugs. Older and currently less commonly used drugs include procainamide (Procanâ ), quinidine (Quinagluteâ ), disopyramide (Norpaceâ ). Occasionally used are the drugs propafenone (Rythmolâ ), and flecainide (Tambocorâ ). Perhaps the most commonly used antiarrhythmic drugs today include sotalol (Betapaceâ ), and amiodarone (Cordaroneâ , Paceroneâ ). These drugs all have significant benefit when used in control of symptomatic cardiac arrhythmias. However, serious potential side effects require close follow up. NITRATES Nitroglycerin and its relatives have been commonly used in the treatment of coronary heart disease. Nitroglycerin and nitrates are very useful in treating acute episodes of chest pain (angina). Nitroglycerin can also be given intravenously as well as in a variety of long acting oral preparations. Nitroglycerin is also absorbed very well through the skin and therefore may also be given as Nitropaste as well as Nitroglycerin skin patches. The major side effect of nitrate use is headache. Nitrates also lower blood pressure and therefore dizziness may occasionally be seen. Nitroglycerin preparations should not be stopped suddenly as they may lead to a heart attack. One should only stop this family of drugs on the recommendation of one's physician and then do so gradually.
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