Through Thick and Thin: Using Anticlotting Drugs

Helping patients understand their regimen can boost adherence.

What are anticlotting agents? They are medications that are used to prevent clots from forming in the blood or to shrink clots that have already formed. You may have heard these medications called “blood thinners.” There are different types—antiplatelets and anticoagulants—and the reason why a person may have to take them depends on the doctor’s diagnosis.

Anticlotting drugs are very important, even though taking them may not make you feel any different. Severe consequences could occur if treatment is not taken seriously. For many people, adding this drug regimen—and sticking to it—is lifesaving.

Blood Clot Basics

There are many proteins, chemicals, and clotting factors in blood that are normally in balance, allowing your blood to flow properly and nourish your cells. Some help the blood clot when you get an injury, and others break the clots down when you are healing. This is normal. Problems arise when clots form and fail to dissolve.

Clots in the veins can occur when there is low blood flow, along with too much clotting factor in the blood. Clots in the arteries happen due to artery plaque buildup and cardiovascular disease. These situations can become damaging and even life threatening, especially when the clots block blood circulation from the legs or major organs such as the brain, the heart, or the lungs. Dangerous clots can occur without warning.

In the brain, a clot is known as a stroke, and in the heart, it is called a myocardial infarction or heart attack. You may be at higher risk for a heart attack or stroke if you:

• Are older or are a man

• Have a family history or previous history of heart attack or stroke

• Have certain conditions, such as diabetes, irregular heartbeats, high blood pressure, high cholesterol, or plaque in your arteries

• Are obese

• Use alcohol or tobacco

• Are sedentary (do not exercise)

In the lungs, a clot is called a pulmonary embolism (or PE), and in the legs, it is known as a deep vein thrombosis (or DVT). The risk for these conditions doubles every decade past 50 years of age. You may also be at higher risk for a PE or DVT if you:

• Have a history of a PE or DVT

• Have hip or knee replacement surgery

• Are pregnant or take drugs containing estrogen

• Use tobacco

• Have a severe illness or cancer or are bedridden or paralyzed

To prevent these events from happening, your doctor will prescribe you medications that he or she thinks will be the safest and most effective for you. Remember that medication alone is not the only answer to improving your health. It is very important for you to have a healthy lifestyle with proper nutrition and exercise.

Anticlotting Drugs

Anticoagulants such as warfarin, heparins, fondaparinux, or dabigatran work by blocking vitamin K or inactivating other clotting factors in the blood. Antiplatelets such as aspirin, dipyridamole, ticlopidine, and clopidogrel prevent clotting by blocking thromboxane, a chemical that rounds up clotting cells in the blood.

These medications all require careful management because they “thin out” your blood and can make you bleed more easily. Avoiding situations where you may fall or become injured is crucial to preventing these serious bleeding events.

What Should I Watch Out For?

If you notice unusual bleeding, such as blood in your urine or stool, if you are coughing up or vomiting blood, or if you have unexplained severe bruising, skin color changes, headache, dizziness, reoccurring nosebleeds, or heavier than normal menstrual bleeding, seek medical attention. There are specific instructions on how you can manage each medication, so talk to your doctor or pharmacist for more details

Ms. Chen is a PharmD candidate at the Ernest Mario School of Pharmacy at Rutgers University, and Dr. Prescott is vice president of Clinical and Scientific Affairs for Pharmacy Times.