Heart Disease Drug Therapy

Angiotensin II receptor blockers are used to treat high blood pressure. These drugs block the action of an enzyme (angiotensin II) that makes the blood vessels get narrower. They work more directly than ACE inhibitors and may cause fewer side effects.

Angiotensin II receptor blockers may be combined with ACE inhibitors but are sometimes used alone in people who cannot take ACE inhibitors.

If these medications are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Drugs to manage high blood pressure or a heart condition
  
• Diuretics
• Medicines, vitamins or salt substitutes that contain potassium
• Over-the-counter drugs for hay fever, colds or flu

Patients should not drink alcohol while taking these drugs without talking to the doctor first. Alcohol combined with angiotensin II receptor blockers can make the blood pressure lower than it should be, causing dizziness or faintness.

Antiarrhythmics are used to treat disorders of the heart's rhythm, such as arrhythmias or atrial fibrillation. These disorders cause heart palpitations, irregular heartbeats, fast heartbeats, lightheadedness, fainting, chest pain and shortness of breath.

Different types of antiarrhythmics work in different ways. Generally, they slow the electrical impulses in the heart so that the heart can return to a regular rhythm. The four types of antiarrhythmic drugs are:

• Sodium-channel blockers, which slow the conduction of electrical impulses in the heart
• Beta blockers, which block the impulses that may cause an irregular heart beat by interfering with hormonal influences (such as adrenaline) on the heart's cells. These actions reduce the blood pressure and heart rate.
• Potassium-channel blockers, which slow the electrical impulses in the heart
• Calcium-channel blockers, which work much the same as beta blockers do

Because each type of antiarrhythmic drug has a slightly different effect, patients may need to work closely with the doctor and try more than one before finding what works best. Sometimes these types of drugs can cause more arrhytmias or make them worse, so the patient would need to be monitored over the course of a 24-hour period using a Holter monitor or by doing electrophysiology studies.

If these medications are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially blood-thinning drugs, such as warfarin, digoxin or insulin (either by injection or orally), because some antiarrhythmic drugs can interact with them. Some antiarrhythmic drugs can also cause sensitivity to sunlight, making patients more prone to sunburn.

Anticoagulants do not actually make the blood thinner. These drugs prevent the blood from forming clots, which can block arteries, veins or the valves of the heart. Common anticoagulants are aspirin, warfarin and heparin.

Anticoagulants help reduce the risk for heart attack, stroke and blockages in veins and arteries, such as ones caused by phlebitis. While these types of drugs can prevent a clot from forming, they do not have an impact on a clot that already exists.

Blood-thinning drugs are given to people who have had a heart valve replaced or who have atrial fibrillation or congestive heart failure. These may be given to a person who is at risk of having a heart attack to prevent blood clots in the arteries of the heart or to people who are at risk of a clot forming in the heart's chambers.

Certain types of drugs (including some over-the-counter pain relievers, such as aspirin) can combine with anticoagulants to cause an even greater anti-clotting effect. If anticoagulants are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Antacids
• Antiarrhythmics
• Antibiotics
• Anticonvulsive drugs
• Antidepressants
• Antihistamines
• Aspirin, acetaminophen (Tylenol®, Excedrin®), ibuprofen (Motrin®, Advil®) or naproxen (Aleve®)
• Calcium or vitamin K supplements
• Corticosteroids, such as prednisone or cortisone-like medications
• Medicines for treating an overactive thyroid
• Sleeping pills
• Some antifungal medicines

Smoking and drinking alcohol can also make the effect of blood-thinning drugs more powerful. Be aware that vitamin K (which is found in fish, liver, spinach, cabbage, cauliflower and Brussels sprouts) can make blood-thinning drugs less effective. Patients who eat these foods must be careful not to eat too much.

Conditions that put the patient at risk of bleeding or bruising require particular caution and should be discussed with the doctor. These include:

• Aneurysms
  
• Cancer
• Diabetes
• Heavy menstrual periods
• Hemophilia or other bleeding conditions
• Kidney or liver disease
• Sports
• Stomach ulcers or other problems
• Stroke or transient ischemic attack
• Surgery (including dental surgery)

Beta blockers block the effect of adrenaline (the hormone norepinephrine) on the body's beta receptors. This slows down the nerve impulses that travel through the heart.

As a result, the resting heart rate is lower, the heart does not have to work as hard and the heart requires less blood and oxygen. Beta blockers can also block the impulses that can cause an arrhythmia (irregular heartbeat).

This type of drug is generally prescribed for:

• High blood pressure
  
• Congestive heart failure
• Abnormal heart rhythms (arrhythmias)
• Chest pain (angina)

If these medications are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Allergy shots
• Antidepressants
• Drugs for treating asthma, chronic bronchitis and emphysema
• Insulin and other medicines used to treat diabetes
• Medicines for high blood pressure, which may increase the effect of beta blockers

The doctor should be told if the patient has:

• A slow heart rate (bradycardia) or heart block
  
• Allergies to foods or dyes, which can be made worse by beta blockers
• An overactive thyroid
• Asthma, which beta blockers can make worse
• Diabetes or hypoglycemia because beta blockers can cause the blood sugar levels to rise or hide the symptoms of low blood sugar
• Heart disease or poor circulation in the hands or feet
• Kidney or liver disease
• Symptoms of hay fever, chronic bronchitis or emphysema

Patients should avoid foods and beverages that have caffeine, antacids that have aluminum or over-the-counter cough and cold medications and antihistamines. Alcohol should also be avoided because it can decrease the effects of the beta blockers.

To learn more about these types of drugs and their side effects, visit Medline Plus (beta blockers)

Calcium-channel blockers cause the blood vessels to relax by slowing the rate at which calcium passes into the heart muscle and blood vessel walls. As the blood vessels relax, more blood can flow through them, lowering the blood pressure. Calcium-channel blockers are prescribed to manage high blood pressure, chest pain (angina) or irregular heartbeats (arrhythmia).

If these medications are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Antiarrhythmics
• Anti-inflammatory drugs, such as corticosteroids
• Calcium
• Digitalis
• Diuretics
• High blood pressure medicine (particularly beta blockers and ACE inhibitors)
• Medications for certain eye conditions
• Vitamin D

The doctor should be told if the patient has:

• Allergies to foods or dyes
• Very low blood pressure
• Heart failure or other heart or blood vessel conditions
• Arrhythmia
• Kidney or liver disease
• Low blood sugar because calcium-channel blockers can make this condition worse
• Parkinson's disease
• A history of depression

Patients should avoid smoking, which may cause a rapid heartbeat (tachycardia), and should wait at least four hours after taking a calcium-channel blocker before eating grapefruit or drinking grapefruit juice, which may interfere with the body's ability to absorb calcium-channel blockers.

If cholesterol levels cannot be brought down to healthy levels by diet and exercise, cholesterol-lowering drugs may be helpful. They are also prescribed for people who have inherited a medical condition that causes high cholesterol.

The four types of cholesterol-lowering drugs are:

• Fibrates (fibric acid derivatives), such as Atromid-S® or Tricor®. These drugs break down the particles that make triglycerides and use them in other ways in the body. Lower triglycerides can lead to increased levels of high-density lipoprotein (HDL).
• Niocin or nicotinic acid, such as Niacor® or Slo-Niacin®. Niacin is a form of vitamin B. It slows the liver's production of certain chemicals that help make low-density lipoprotein (LDL) cholesterol. Niacin also helps lower triglycerides and raise HDL.
• Resins (bile acid sequestrants), such as Colestid® or Questran®. Cholesterol helps in the production of bile, an acid used in digestion. This type of cholesterol-lowering drug binds to bile so it cannot be used during digestion, forcing the liver to make more bile. The more it makes, the more cholesterol it uses, leaving less cholesterol to circulate in the blood.
• Statins (HMG-CoA reductase inhibitors), such as Lipitor®, Mevacor® or Zocor®. These drugs work by blocking an enzyme (HMG-CoA reductase) that helps the body make cholesterol. When the body produces less cholesterol, it signals the liver to make more LDL receptors. These receptors attract the LDL particles in the blood, reducing the amount of LDL cholesterol circulating in the blood. When the LDL level falls, the triglyceride levels fall and the HDL cholesterol increases.

If these medications are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Warfarin, an anticoagulant, which can interact with cholesterol-lowering medications and may require that dosages of both be adjusted
  
• Erythromycin
• Certain antifungal medicines

Patients should avoid drinking and taking statins until they have talked about it with the doctor. The doctor should be told if the patient has:

• Liver problems
  
• Diabetes, gout or ulcers because nicotinic acid can make these worse
• Kidney disease or gall bladder disease, particularly if prescribed a fibric acid derivative
• Been thinking about becoming pregnant or already is pregnant

Digitalis increases the force of each heartbeat by increasing the amount of calcium in the heart's cells. It can control irregular heart rhythms (arrhythmias) by slowing the signals that start in the sinoatrial node, which reduces the number of signals that travel through the atrioventricular node and reduces irregular heartbeats.

Digitalis increases blood flow throughout the body and can reduce swelling in the hands and ankles caused by blood pooling there when the heart does not pump efficiently. It is prescribed for persons who have congestive heart failure and heart rhythm problems, such as atrial fibrillation.

If this medication is prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Antacids
  
• Anti-anxiety medicines
• Antiarrhythmia medicines
• Antibiotics
• Calcium-channel blockers
• Certain antifungal medicines
• Colitis drugs
• Diarrhea medicines
• Diuretics
• Other heart medicines
• Some cancer medicines
• Some cholesterol-lowering medicines especially cholestyramine
• Ulcer or stomach medicines

Patients should avoid caffeine, diet pills and laxatives, as well as cough, cold or sinus medicines. The doctor should be told if the patient has:

• Allergies to digitalis medicines, foods or dyes
• Have other health conditions, such as thyroid disease, liver disease, lung disease or kidney disease
• Been thinking about becoming pregnant or already is pregnant

To learn more about these types of drugs and their side effects, visit Medline Plus (digitalis)

Diuretics reduce the amount of salt and water in the body. As the kidneys filter the excess water from the blood, the volume of blood the heart has to pump is reduced, causing blood pressure to go down.

Diuretics are given when the have congestive high blood pressure, swelling or water retention (edema) or heart failure. They may also be prescribed for certain kinds of kidney or liver disease. Diuretics can be very useful for people who are older or obese.

There are three types of diuretics:

• Loop-acting diuretics, such as Bumex®, Demadex®, Edecrin® or Lasix®. These cause the kidneys to get rid of more urine, lowering the amount of water in the body and the blood pressure.
  
• Potassium-sparing diuretics, such as Aldactone®, Dyrenium® or Midamor®. These drugs reduce the amount of water in the body, but while other diuretics cause the body to lose potassium in the process, this type does not. This type of diuretic is often prescribed with another diuretic because, while it spares potassium, it does not control blood pressure as well as thiazide diuretics do.
• Thiazide diuretics, such as Aquatensen®, Diucardin® or Trichlorex®. This type of diuretic reduces the amount of salt and water in the body. It is also the only type of diuretic that widens the blood vessels to lower blood pressure. Thiazide diuretics are often the first drug given to treat high blood pressure.

If diuretics are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Antidepressants, particularly when taking thiazide or loop-acting diuretics
  
• Clyclosporine, particularly if taking a potassium-sparing diuretic
• Digitalis, particularly for patients with low potassium levels
• Lithium
• Other medications for high blood pressure

The doctor should be told if the patient has:

• A tendency to become dehydrated easily
  
• Allergies to other medicines
• Been thinking about becoming pregnant or already is pregnant
• Diabetes because thiazide and loop-acting diuretics can increase the blood sugar levels
• Gout or are a high risk of developing gout, especially if the doctor is considering prescribing a thiazide diuretic
• Kidney problems
• Lupus because thiazide diuretics can make this worse
• Pancreatitis because loop-acting diuretics make this worse

To learn more about these types of drugs and their side effects, visit:

• Medline Plus (loop-acting diuretics)
  
• Medline Plus (thiazide diuretics)
• Medline Plus (potassium-sparing diuretics)

Nitrates are used to treat chest pain associated with angina and to reduce the symptoms of congestive heart failure. They are called vasodilators because they cause the blood vessels to widen. This makes the blood flow better, reduces blood pressure, reduces the workload on the heart and allows more oxygen-rich blood to reach the heart muscle.

If nitrates are prescribed, the doctor should be made aware of any other drug, vitamin, mineral or herbal supplement the patient is taking, especially:

• Certain heart medicines
  
• Medications for high blood pressure
• Over-the-counter cough, cold and flu medicines
• Over-the-counter herbal cough, cold and flu medicines
• Viagra® (sildenafil). When mixed with nitrates, Viagra can lower the blood pressure, making the patient dizzy, lightheaded or faint. In some cases, Viagra taken with nitrates has caused death. Patients should not take Viagra within 24 hours of taking nitrates.

Patients should avoid smoking when taking nitrates. Smoking can decrease the effect of the medicine. Alcohol should be avoided because it can increase the effect of nitrates.

The doctor should be told if the patient has:

• An overactive thyroid
• Anemia
• Been thinking about becoming pregnant or already is pregnant
• Frequent, severe headaches
• Glaucoma
• Liver or kidney disease
• Recently had a heart attack
• Recently had a stroke

To learn more about these types of drugs and their side effects, visit:

• Medline Plus (oral nitrates)
  
• Medline Plus (topical nitrates)
• Medline Plus (lingual nitrates)