Table of Contents

I. What Do Blood Thinners Do?

II. Side Effects of Blood Thinners

III. Gastroprotection

IV. Mixing Medications

V. Informing Healthcare Providers

VI. Avoiding Injuries

VII. Blood Thinners and Alcohol

VIII. FAQ: How Can I Reduce Bleeding Risk While Taking Blood Thinners?

What Do Blood Thinners Do? 

Blood thinners are medicines that help prevent blood clots from forming and keep existing clots from getting bigger. They may be prescribed for people with certain heart or blood vessel conditions, atrial fibrillation, heart valve replacements, congenital heart defects, or a higher risk of blood clots after surgery. [1] Examples of anticoagulants include Xarelto (rivaroxaban), Coumadin (warfarin), and Eliquis (apixaban). [2]

Despite their name, blood thinners do not actually make the blood thinner. Anticoagulants work by interfering with the body's clotting process. For example, warfarin reduces the production of vitamin K dependent clotting factors, while rivaroxaban and apixaban block factor Xa. [2]

Side Effects of Blood Thinners

Bleeding is the most common side effect of blood thinners. [1] Signs of serious bleeding can include:

• Heavy menstrual bleeding
• Red or brown urine
• Red or black bowel movements
• Bleeding from the gums or nose that does not stop quickly
• Vomiting blood
• Coughing up blood
• Unusual bruising
• A cut that does not stop bleeding
• Dizziness or weakness [1]

You should also seek emergency medical care after a serious fall or hit to the head, or if you experience symptoms such as chest pain, shortness of breath, uncontrolled bleeding, or extensive bruising while taking an anticoagulant. [3]

Gastroprotection 

Blood thinners can increase the risk of gastrointestinal (GI) bleeding. Taking more than one blood-thinning medication may increase this risk. However, some people do need to take more than one blood thinner because of their medical condition. In some cases, a doctor may recommend a proton pump inhibitor (PPI), such as omeprazole, to reduce stomach acid and help lower the risk of GI bleeding. Not everyone needs a PPI, so talk to your doctor before making any changes to your medications. [4]

Mixing Medications 

Some antibiotics and antifungal medications can interact with Coumadin (warfarin) and increase the risk of bleeding. Examples include cotrimoxazole, cephalexin, penicillin, itraconazole, and ketoconazole. [5]

If you take warfarin and are prescribed an antibiotic or antifungal medication, tell your doctor or healthcare provider. Your provider may need to check your INR and adjust your warfarin dose if needed. [5]

Informing Healthcare Providers

Tell all of your doctors, dentists, and pharmacists that you take a blood thinner. This is important because blood thinners can interact with other medicines and treatments. [6]

Keep an updated list of your prescription medicines, over-the-counter medicines, vitamins, and herbal products, and share it with your healthcare providers. If you start or stop a medicine, or your dose changes, let your doctor know. [6]

Avoiding Injuries

Blood thinners can increase your risk of bleeding, so it is important to take steps to avoid falls and injuries. Be careful when using sharp objects such as knives, scissors, or razors, and avoid activities or sports that could easily cause an injury. [6]

You can still stay active while taking a blood thinner. Walking and swimming are examples of safer activities but talk to your doctor before starting a new exercise or activity. [6]

Blood Thinners and Alcohol

Alcohol can interact with blood thinners and increase the risk of bleeding. Drinking too much alcohol can affect how your liver handles medications, which may make them more or less effective. This is especially important with warfarin. Alcohol can make warfarin more potent and increase the risk of stomach bleeding. Talk to your doctor about whether it is safe for you to drink alcohol while taking a blood thinner. [7]

FAQ: How Can I Reduce Bleeding Risk While Taking Blood Thinners?

To reduce bleeding risk while taking blood thinners, take your medication exactly as prescribed and make sure every healthcare provider you see knows you are taking it. Blood thinners help prevent clots from forming or getting larger, but bleeding is their most common side effect. Serious warning signs can include red or brown urine, red or black stools, vomiting or coughing up blood, unusual bruising, bleeding that does not stop, dizziness, or weakness.

It is also important to avoid medication changes without medical advice. Some prescriptions, over-the-counter products, vitamins, herbal products, antibiotics, antifungals, and alcohol can increase bleeding risk or affect how blood thinners work. If you take warfarin, your doctor may need to check your INR when certain medications are added or changed.

To lower your risk of excessive bleeding:

1. Take your blood thinner exactly as directed.
2. Tell doctors, dentists, and pharmacists that you take a blood thinner.
3. Keep an updated list of all prescriptions, over-the-counter medications, vitamins, and herbal products.
4. Ask your doctor before starting or stopping any medication or supplement.
5. Be careful with sharp objects such as knives, scissors, and razors.
6. Avoid activities or sports that could easily cause injury.
7. Ask your doctor whether alcohol is safe for you.
8. Seek emergency care after a serious fall, a hit to the head, uncontrolled bleeding, chest pain, shortness of breath, or extensive bruising.

The content in this article is intended for informational purposes only. This website does not provide medical advice. In all circumstances, you should always seek the advice of your physician and/or other qualified health professionals(s) for drug, medical condition, or treatment advice. The content provided on this website is not a substitute for professional medical advice, diagnosis, or treatment.