DOACs Explained: What You Need to Know About These Blood Thinners

• DOACs (Direct Oral Anticoagulants) are a newer class of blood thinners used to prevent and treat blood clots.
• They were developed as an alternative to warfarin, which required frequent blood tests, had dietary restrictions, and a high risk of drug interactions.
• There are four main DOACs currently available: Rivaroxaban (Xarelto), Dabigatran (Pradaxa), Apixaban (Eliquis), and Edoxaban (Lixiana).
• Advantages of DOACs include: working quickly, stopping relatively fast, no routine blood monitoring required, fewer interactions with food and other medications, and a predictable effect on blood clotting without the need for INR monitoring.
• Disadvantages of DOACs include: more expensive than warfarin, some requiring twice-daily dosing, and not all having FDA-approved antidotes for immediate reversal. They are also shorter-acting, so missing a dose might increase the risk of clots more quickly than with warfarin.

Direct Oral Anticoagulants (DOACs) are newer types of blood thinners that offer several advantages over warfarin.

Since the 1950s, warfarin has been the primary anticoagulant used to prevent blood clots, strokes, heart attacks, and deep vein thrombosis (DVT). However, warfarin comes with challenges: frequent blood tests, dietary restrictions, and a high risk of interactions with other medications.

DOACs became popular in the early 2010s because they do not require frequent blood tests and are not affected by dietary intake.

Currently Available DOACs

• Rivaroxaban (Xarelto)
• Dabigatran (Pradaxa)
• Apixaban (Eliquis)
• Edoxaban (Lixiana)

Advantages of DOACs

• Rapid onset of action: Start working quickly after the first dose.
• Relatively short duration of action: Stop working relatively fast after discontinuation.
• No routine blood monitoring.
• Fewer interactions with food, supplements, and other medications.
• Predictable effect on blood clotting, eliminating the need for international normalized ratio (INR) monitoring. Unlike warfarin, which requires frequent blood tests to maintain INR levels within a safe range, DOACs work consistently at fixed doses.

Disadvantages of DOACs

• More expensive compared to warfarin.
• Some require twice-daily dosing, which can lead to missed doses.
• Short-acting: Missing a dose could increase the risk of clot formation more quickly than with warfarin
• Not all DOACs have FDA-approved antidotes for immediate reversal.

How DOCAs Work

Blood clotting is a natural process that helps stop bleeding after an injury. It involves a series of steps where proteins in your blood, known as clotting factors, work together to form a clot. When clots form in places where they shouldn’t, it can lead to serious health problems like heart attack or stroke.

Direct oral anticoagulants (DOACs) regulate clot formation by directly targeting specific clotting factors, unlike warfarin, which works by inhibiting vitamin K. This direct action provides a more predictable and consistent anticoagulant effect.

DOACs target two key clotting factors:

• Thrombin (Factor IIa) Inhibition: Thrombin plays a crucial role in converting fibrinogen to fibrin, the structural foundation of a blood clot.
  Example: Dabigatran (Pradaxa)
• Factor Xa Inhibition: Factor Xa is another essential protein in the clotting cascade.
  Examples: Rivaroxaban (Xarelto), apixaban (Eliquis), and edoxaban (Lixiana)

What Are DOACs Used For?

DOACs are prescribed to lower your risk of blood clots that can lead to serious health problems. These medications help prevent clots from forming or getting larger, reducing complications associated with following medical conditions:

• Atrial Fibrillation (AFib): An irregular heart rhythm that increases your risk of stroke.
• Deep vein thrombosis (DVT): A blood clot in a deep vein, usually in the leg.
• Pulmonary embolism (PE): A blood clot travels to your lungs and blocks blood flow. It can cause breathing problems, chest pain, and in severe cases, be fatal.
• Stroke risk reduction : In patients with high blood pressure, smoking, and diabetes.
• Peripheral artery disease (PAD): Narrowed arteries reduce blood flow to your legs and feet. Clots can develop in these narrowed arteries, leading to pain, or ulcers.
• Coronary Artery Disease (CAD): Caused by plaque buildup in your arteries supplying your heart. In some cases, clots can form and block these arteries, leading to heart attacks.

Side Effects

DOACs are generally well tolerated, but they can increase your risk of bleeding. Some effects are mild, while others require immediate medical attention.

Common Side Effects

These side effects are more frequent but usually not dangerous:

• Bruising: Minor bruises may appear more easily and take longer to fade.
• Prolonged bleeding: Small cuts or nosebleeds may last longer than usual. Applying firm pressure can help stop minor bleeding.
• Stomach discomfort: Some may experience indigestion or mild stomach irritation.

Serious Side Effects

Get immediate medical attention if any of the following occur:

• Uncontrolled or frequent bleeding: This includes frequent nosebleeds, heavy menstrual bleeding, or unexplained gum bleeding.
• Vomiting blood or coughing up blood: Blood may appear bright red or resemble coffee grounds.
• Unusual bruising or rapidly growing bruises: Large bruises or those appearing without injury may be a sign of internal bleeding.
• Blood in stool or urine: Black, tar-like stool or red streaks in the toilet may indicate internal bleeding. Urine may appear pink, red, or brown.
• Severe headaches or dizziness: These could be signs of bleeding in your brain and require urgent evaluation.

Risks

• Pregnancy risk: Some DOACs have been linked to potential fetal harm in animal studies. Pregnant women or those planning a pregnancy should discuss alternative options with their doctor.
• Medication and supplement interactions: Taking DOACs with aspirin, ibuprofen, naproxen, or certain supplements can further increase bleeding risk. Any additional medications should be discussed with your provider.
• Medical identification: Wearing a medical bracelet or carrying an ID card that states the use of anticoagulants can help emergency personnel provide appropriate treatment if needed.

Speak with Your Doctor

DOACs have become a widely used option for preventing and treating blood clots, providing a more convenient alternative to older blood thinners.

Although they do not require routine blood monitoring and have fewer interactions with food and other medications, they are not always right for everyone. Factors such as overall health, medical history, and potential bleeding risks should be considered before starting treatment.

If you have concerns about DOACs, including their benefits, risks, or how they compare to other blood thinners, speak with your doctor. They can help determine whether a DOAC is the best choice for you and provide guidance on how to take it safely.