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How to use blood thinners safely
Blood thinners can help prevent dangerous blood clots—like those that cause heart attacks and strokes. But they also have side effects that you need to be aware of.
If your doctor prescribes blood thinners, the following tips can help you use them safely.
TAKE YOUR BLOOD THINNER JUST AS DIRECTED
Taking your blood thinner exactly as prescribed can help you have the most benefit with the least risk of side effects, such as bleeding. Take your medicine at the same time every day. Never skip a dose or take a double dose because you missed a dose. If you miss a dose, ask your doctor what to do. Consider using a pillbox or a calendar to help you remember to take your blood thinner.
TELL ALL YOUR PROVIDERS THAT YOU TAKE BLOOD THINNERS
Some medicines and blood thinners can interact with each other, and blood thinners can increase the risk of bleeding during dental or medical procedures. This is why it's important to tell every healthcare provider you see that you're on a blood thinner. Also, you should tell the doctor who prescribed your blood thinner about any other medicines you're taking, including over-the-counter pain remedies, vitamins, minerals and herbs.
REPORT SIDE EFFECTS RIGHT AWAY
Bleeding (which can occur internally) is a potential side effect of blood thinners. Call your doctor if you experience possible signs or symptoms of unusual bleeding, such as:
- Heavy menstrual bleeding.
- Bleeding that doesn't stop.
- Red or brown urine or red or black stools.
- Bad headaches or stomach pains.
- Dizziness or weakness.
PRACTICE SAFE HYGIENE
Take care not to cut or injure yourself during personal care activities, since even small cuts can cause excessive bleeding. For example:
- Use an electric shaver.
- Choose a soft toothbrush and waxed dental floss.
- Never use toothpicks.
- Be extra careful when trimming your toenails.
- Have your doctor trim any corns or callouses for you.
AVOID CONTACT SPORTS AND OTHER ACTIVITIES THAT CAN CAUSE INJURIES
Choose activities that aren't likely to hurt you and cause bleeding. Walking, swimming and biking (with a helmet) are usually safe. If you work around the yard or with tools, wear proper gloves and footwear to protect against cuts or scrapes.
Finally, if you fall or hurt yourself, call your doctor, even if you don't see any bleeding.
WATCH WHAT YOU EAT AND DRINK
Don't drink alcohol when you're taking a blood thinner. It raises your risk of bleeding. Also, talk to your healthcare provider about the foods you eat. Vitamin K-rich foods (such as broccoli, leafy greens, Brussels sprouts, fish and cabbage) can interfere with some blood thinners. You don't have to avoid these foods, but you could have problems with your blood thinner if you start eating a lot of them.
WEAR A MEDICAL ID ALERT
In a medical emergency, such as a car crash, you might not be able to speak for yourself. A medical alert bracelet or necklace would tell the paramedics and doctors who care for you that you're on a blood thinner. They need to know that to give you the right care.
HAVE YOUR BLOOD TESTED REGULARLY
When you're on blood thinners, you usually need regular testing to see how well your medicine is working. Over time, your doctor may need to adjust your dose based on your test results. The goal is for your blood thinner to reduce your blood's tendency to clot without causing bleeding.
Get simple tips to help you remember to take your medicines.
Sources: Agency for Healthcare Research and Quality ; American Heart Association
- Agency for Healthcare Research and Quality. "Blood Thinner Pills: Your Guide to Using Them Safely." https://www.ahrq.gov/patients-consumers/diagnosis-treatment/treatments/btpills/btpills.html.
- American Heart Association. "A Patient's Guide to Taking Warfarin." https://www.heart.org/en/health-topics/arrhythmia/prevention--treatment-of-arrhythmia/a-patients-guide-to-taking-warfarin.
- UpToDate. "Patient Education: Warfarin (Beyond the Basics)." https://www.uptodate.com/contents/warfarin-beyond-the-basics.