What are blood thinners?

Blood thinners are drugs that prevent the blood from clotting. They’re also called anticoagulants. “Coagulate” means “to clot.”

Blood clots can block the flow of blood to the heart or brain. A lack of blood flow to these organs could cause a heart attack or stroke.

Having high cholesterol increases your risk of a heart attack or stroke due to a blood clot. Taking a blood thinner might help lower that risk. These drugs are mainly used to prevent blood clots in people with an abnormal heart rhythm, called atrial fibrillation.

Warfarin (Coumadin) and heparin are older blood thinners. Five new blood thinners are also available:

  • apixaban (Eliquis)
  • betrixaban (Bevyxxa, Portola)
  • dabigatran (Pradaxa)
  • edoxaban (Savaysa)
  • rivaroxaban (Xarelto)

How do blood thinners work?

Blood thinners don’t actually thin the blood. Instead, they prevent it from clotting.

You need vitamin K to produce proteins called clotting factors in your liver. Clotting factors make your blood clot. Older blood thinners like Coumadin prevent vitamin K from working properly, which reduces the amount of clotting factors in your blood.

New blood thinners like Eliquis and Xarelto work differently — they block factor Xa. Your body needs factor Xa to make thrombin, an enzyme that helps your blood clot.

Are there any risks or side effects?

Because blood thinners prevent the blood from clotting, they could cause you to bleed more than usual. Sometimes the bleeding can be severe. Older blood thinners are more likely to cause excessive bleeding than new ones.

Call your doctor if you notice any of these symptoms while taking blood thinners:

  • new bruises without a known cause
  • bleeding gums
  • red or dark brown urine or stool
  • heavier-than-normal periods
  • coughing up or vomiting blood
  • weakness or dizziness
  • severe headache or stomachache
  • a cut that won’t stop bleeding

Blood thinners can also interact with certain medications. Some drugs increase the effects of blood thinners and make you more likely to bleed. Other drugs make blood thinners less effective at preventing a stroke.

Let your doctor know before you take an anticoagulant if you’re taking any of these medications:

  • antibiotics such as cephalosporins, ciprofloxacin (Cipro), erythromycin (Erygel, Ery-tab), and rifampin (Rifadin)
  • antifungal drugs like fluconazole (Diflucan) and griseofulvin (gris-PEG)
  • the anti-seizure drug carbamazepine (Carbatrol, Tegretol)
  • antithyroid medication
  • birth control pills
  • chemotherapy drugs like capecitabine
  • the cholesterol-lowering drug clofibrate
  • the gout drug allopurinol (Aloprim, Zyloprim)
  • the heartburn relief drug cimetidine (Tagamet HB)
  • the heart rhythm drug amiodarone (Nexterone, Pacerone)
  • the immune-suppressing drug azathioprine (Azasan)
  • pain relievers such as aspirin, diclofenac (Voltaren), ibuprofen (Advil, Motrin), and naproxen (Aleve)

Also let your doctor know if you’re taking any over-the-counter (OTC) medications, vitamins, or herbal supplements. Some of these products can also interact with blood thinners.

You may also want to consider monitoring how much vitamin K you’re getting in your diet. Ask your doctor how much food containing vitamin K you should eat each day. Foods that are high in vitamin K include:

  • broccoli
  • Brussels sprouts
  • cabbage
  • collard greens
  • green tea
  • kale
  • lentils
  • lettuce
  • spinach
  • turnip greens

How does high cholesterol increase heart attack and stroke risk?

Cholesterol is a fatty substance in your blood. Your body makes some cholesterol. The rest comes from the foods you eat. Red meat, full-fat dairy foods, and baked goods are often high in cholesterol.

When you have too much cholesterol in your blood, it can build up in your artery walls and form sticky blockages called plaques. Plaques narrow the arteries, allowing less blood to flow through them.

If a plaque rips open, a blood clot can form. That clot could travel to the heart or brain and cause a heart attack or stroke.

Outlook

Having high cholesterol increases your risk of heart attack or stroke. Blood thinners are one way to prevent clots from forming. Your doctor might prescribe you one of these drugs if you also have atrial fibrillation.

A normal total cholesterol level is below 200 mg/dL. The ideal LDL cholesterol level is less than 100 mg/dL. LDL cholesterol is the unhealthy type that forms plaques in arteries.

If your numbers are high, you can make these lifestyle changes to help bring them down:

  • Limit the amount of saturated fat, trans fat, and cholesterol in your diet.
  • Eat more fruits and vegetables, fish, and whole grains.
  • Lose weight if you are overweight. Taking off just 5 to 10 pounds can help bring down your cholesterol levels.
  • Do aerobic exercises like bike riding or walking for 30 to 60 minutes each day.
  • Stop smoking.

If you’ve tried making these changes and your cholesterol is still high, your doctor might prescribe statins or another medication to lower it. Follow your treatment plan closely to protect your blood vessels and reduce your risk of a heart attack or stroke.