March 19, 2024/Primary Care

What To Avoid When Taking a Blood Thinner

Bleeding is a risk and warrants taking care, but the reward of this lifesaving medication is great

anticoagulant pills

Sometimes, blood clots are a good thing. They protect you from bleeding too much if you’re injured or have surgery. But sometimes, blood clots form for other reasons, like being on bed rest or in the hospital for a long time, having a weight that’s not healthy for you, being genetically predisposed to blood clots or having a blood clotting disorder. Pregnancy, cancer and estrogen therapy can also put you at a greater risk of forming a clot.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Then, instead of helping, the clots become harmful because they keep blood from flowing through your veins and arteries as it should. And that can lead to some serious stuff, like stroke, heart attack or pulmonary embolism.

Despite their name, blood thinners (also called anticoagulants) don’t actually thin your blood. They work by keeping your blood from sticking together in a clump (clotting). Blood thinners keep a clot where it is and from getting bigger and prevent new clots from forming. They can also allow your body to absorb the clot through the walls of your veins over time.

But because they stop your blood from clotting, you also run the risk of bleeding too much if you cut yourself, get injured or need surgery. So, how do you minimize the risk while reaping the reward?

How to stay safe when you take a blood thinner

Blood thinners are indeed lifesaving. According to the National Blood Clot Alliance (NBCA), in the U.S., more than 8 million people currently take them.

Vascular medicine specialist Jay Bishop, MD, explains what to avoid if you take a blood thinner so you stay safe while they work their magic.

Participating in risky activities

Doing anything that can make you bleed is something to seriously consider not doing if you’re on a blood thinner. That means contact sports like hockey, soccer or football, or ones that pose a serious risk of injury if you fall (like skiing, gymnastics or ice skating) are best put on the sidelines. Swimming or walking for exercise are better options.

And if you like to bike, that’s cool, but “Don’t forget your helmet,” reminds Dr. Bishop. Or try a spin class at your local gym.

It’s not just sports, though. Anything that can cause injury and bleeding — even the simplest daily tasks — can be risky business if you’re on a blood thinner, explains Dr. Bishop. So, to prevent mishaps, you should:

  • Be extra careful using knives or scissors.
  • Use an electric razor.
  • Use a soft toothbrush.
  • Be careful when you trim your nails.
  • Use waxed dental floss.
  • Stay away from toothpicks.
  • Wear shoes or slippers inside.
  • Wear gloves when gardening or using outdoor tools.

Eating foods with too much vitamin K

Vitamin K helps your body develop and work properly, which is an important job. But it also helps your blood to clot, which means if you’re on a blood thinner, vitamin K could be working against you.

“It’s important to understand drug-food interactions when you’re taking a blood thinner like warfarin (Coumadin®) the most common one,” warns Dr. Bishop.

If you’re taking warfarin, you don’t have to give up foods higher in vitamin K completely. But limiting them in your diet and being consistent in the portions you do eat is important. Changing up how much vitamin K you’re getting each day can prevent warfarin from doing its job.

Green tea also contains some vitamin K, so it’s best to choose another option, like black tea, which doesn’t interact with a blood thinner.

Foods lower in vitamin K include:


Consuming certain fruits and juices

“If you’re on some blood thinners, studies show you should also stay clear of cranberry, grapefruit and pomegranate fruits and juices,” advises Dr. Bishop.

Like vitamin K, these all contain compounds that can counteract the good things that blood thinners do. Craving something citrusy? Grab an orange or a glass of OJ instead. Watermelon, apples, bananas, pears and peaches are also safe fruit choices.

Drinking too much alcohol

Of course, if you drink alcohol, drinking in moderation is always recommended. But it’s especially important if you’re on a blood thinner. Over-imbibing can affect how quickly your blood clots and can increase your chances of falling. Even a simple fall can give you a nasty bruise or could even cause internal bleeding.

Taking herbal supplements

People have used herbal supplements for centuries for their healing properties. “But if you’re on a blood thinner, they could do more harm than good,” warns Dr. Bishop.

Research shows that taking certain herbal supplements can make it harder for your blood to clot. And that can make it more likely for you to bleed severely — both inside and outside your body — if you get hurt. So, if you’re on a blood thinner, you shouldn’t use supplements like ginkgo biloba, garlic, melatonin, turmeric, peppermint oil and St. John’s Wort — to name just a few — before talking with your healthcare provider first.

More don’ts if you take a blood thinner

It’s not just about what not to eat and drink if you’re taking a blood thinner. Here are some more important “don’ts.”


Heads up that some of these “don’ts” don’t apply if you’re on one of the newer blood thinners, like Rivaroxaban (Xarelto®) or Apixaban (Eliquis®). So, it’s important to check with your healthcare provider to make sure you’re taking the appropriate precautions.

  • Don’t take over-the-counter pain relievers, cold medicines and stomach remedies. This includes aspirin, ibuprofen (Advil®), naproxen sodium (Aleve®), Alka-Seltzer®, acetaminophen (Tylenol®), Excedrin® and certain antibiotics and medications for fungal infections, anxiety, depression, seizures and HIV/AIDS. Check with your health professional about any potential interactions, and if the risk outweighs the benefit.
  • Don’t neglect regular monitoring. “If you’re on a blood thinner like warfarin, you’ll need to have your blood tested regularly to see if the medicine is working to keep your blood from being too thin or too thick, and if the dose needs to be changed,” explains Dr. Bishop. But the newer blood thinners don’t require blood tests to monitor levels or targets.
  • Don’t skip a dose or take a double dose. Following your provider’s instructions for using your blood thinner is crucial for the medication to be effective.
  • Don’t schedule certain dental work. Common dental procedures, like cleanings and fillings, don’t typically cause a lot of bleeding, so they can be done safely if you’re on a blood thinner. But your provider may recommend avoiding more complex procedures like getting a tooth pulled or having dental implants placed, which can cause more bleeding that’s harder to control.
  • Don’t Ignore side effects. Always alert your provider if you experience any side effects from your blood thinner, like nausea, fatigue, shortness of breath, dizziness, weakness, skin rashes, swelling of your face, lips, tongue or throat, diarrhea or unusual bruising or bleeding.

So, is the reward worth the risk?

When it comes to protecting you from a possible devastating blood clot, your provider will let you know if a blood thinner is right for you and will talk with you about which kind is your best option. They’ll also help you learn how to minimize the risks of taking a blood thinner so you can reap the rewards without worry.


Learn more about our editorial process.

Related Articles

Male holding pill and glass of water, with assorted alcohol behind him crossed out
April 22, 2024/Primary Care
Why You Should Avoid Alcohol on Antibiotics

Even a little alcohol can slow your recovery, so it’s best to wait until after you finish your antibiotics before imbibing

Birth control pack, with an overlay of a hand holding other pills and tablets
March 13, 2024/Women's Health
What Medications Interfere With Birth Control Pills?

Certain seizure medications, HIV treatments, antibiotics or herbal supplements can make your oral contraception less effective

Variety of medication pills and tablets and liquids
February 22, 2024/Primary Care
Is It OK To Take Expired Medicine?

Some types of expired meds may not be harmful, but they probably aren’t worth the risk

close up of bottle of pills spilling onto table
January 24, 2024/Heart Health
Take Your Cholesterol Meds: Stopping Statins Can Cause Dangerous Side Effects

Stopping this critical medication on your own increases the risk of heart attack, stroke and more

Closeup of hands holding a glass of water and an aspirin
January 16, 2024/Heart Health
Can Aspirin Lower Blood Pressure?

Don’t believe the rumors about aspirin being a magic way to lower BP

Aspirin poured onto table from bottle
December 6, 2023/Allergies
Why You’re Sensitive to Aspirin

A reaction to the medication may trigger preexisting asthma and result in sinus or skin reactions

nocovaine needle entering mouth with dental mirror
December 3, 2023/Oral Health
How Long Does Novocaine Last?

The numbness and tingling should wear off in about two hours

nasal spray
May 15, 2023/Allergies
This Is Why Your Nasal Spray Stopped Working (and What To Do About It)

‘Rebound congestion’ happens when your body starts to rely on decongestant nasal spray

Trending Topics

Person in yellow tshirt and blue jeans relaxing on green couch in living room reading texts on their phone.
Here’s How Many Calories You Naturally Burn in a Day

Your metabolism may torch 1,300 to 2,000 calories daily with no activity

woman snacking on raisins and nuts
52 Foods High In Iron

Pump up your iron intake with foods like tuna, tofu and turkey