Anticoagulants for coronary artery disease

Examples

Unfractionated heparins

Low-molecular-weight heparins

Coumarins

Direct thrombin inhibitors

How It Works

Anticoagulants are often called blood thinners, but they don't really thin blood. They work by increasing the time it takes for a blood clot to form. This prevents an existing clot from increasing in size, thereby preventing a heart attack or stroke.

Why It Is Used

Anticoagulants are often used to prevent blood clots from forming in the heart during or after a heart attack. Anticoagulants also may be given after angioplasty or other revascularization procedures. Heparins are often combined with aspirin and other antiplatelet medications (such as abciximab [ReoPro]) to help reduce the risk of heart attack and death in people who have unstable angina.

These medications are used to help reduce the risk of forming a new blood clot in a blood vessel after angioplasty.

How Well It Works

Anticoagulants are effective in reducing the rate of stroke and recurrent heart attack in people who are having a heart attack. Anticoagulants may lessen the risk of heart attack in people with unstable angina or those who have recently had angioplasty with or without stenting.

Anticoagulants also reduce the risk of stroke in people who have recently had a large heart attack on the front wall of the heart.

Side Effects

Anticoagulants can increase the risk of bleeding or bruising, including:

• Bleeding in the brain.
• Bleeding in the stomach and intestines.

Anticoagulants may cause problems with blood circulation that turn toes (and also possibly abdomen, breasts, and other fatty tissue areas) purple or blue. If this side effect occurs, the drug should be stopped immediately.

Warfarin can cause skin rash problems.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

The low-molecular-weight heparins (such as enoxaparin) are favored over regular heparin because they are given only 1 or 2 times per day and they do not require frequent blood tests to monitor the effects of the medication. However, low-molecular-weight heparins are more expensive.

If you are taking anticoagulants, notify your doctor immediately if you have:

• Blood in your urine.
• Bloody or tarlike (tarry) black stools.
• Unusual bleeding from your nose or gums or if you are spitting up blood.
• Abnormally long menstrual bleeding.
• Unusual bruising or tiny red or purple spots on the skin.

Safety tips when taking anticoagulants may be helpful, such as taking your medications at the same time each day and watching for signs of bleeding.

What to do if you miss a dose of anticoagulant:

• If you remember it in the same day, take the missed dose. Then go back to your regular schedule.
• If it is the next day, or almost time to take the next dose, do not take the missed dose. Do not double the dose to make up for the missed one. At your next regularly scheduled time, take your normal anticoagulant dose.
• If you miss your dose for 2 or more days, call your doctor.

Do not double the dose in any one day to make up for a missed dose. Call your doctor if you are not sure what to do if you missed a dose.

If you are taking certain anticoagulants, it is very important to follow your doctor's specific instructions about when and how often to take them.

Your doctor also may want you to return for lab testing on a regular basis to check the effect of the drug on your blood clotting system.

It is important to avoid other medications that also interfere with blood clotting. Common medications that interfere with blood clotting are aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (for example, Motrin).

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.