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Taking blood thinners safely

Blood thinners can be an important medical treatment. But like all medicines, they come with potential risks. When you're prescribed these medications there are things you can do to protect yourself.

If you've been prescribed a blood thinner, there are two things you should know:

  1. These medications do a good job of preventing blood clots that can lead to heart attack, stroke or other medical problems. If your doctor has prescribed one for you, it's important to take it.
  2. Blood thinners are safe when used as directed. But like all medicines, they come with potential risks. The more you know about the risks, the easier it is to stay safe while taking the medication.

With safety in mind, the Agency for Healthcare Research and Quality, the Institute for Safe Medication Practices and others offer people who are taking blood thinners the following advice:

Be sure every doctor you see, including your dentist, knows about all of the medicines you're taking. Blood thinners can interact with other medications. Aspirin and products containing aspirin, for example, are particularly likely to lead to bleeding when combined with blood thinners. But several other medicines can cause problems as well.

  • Always check with your doctor before taking a new medicine, stopping an existing medicine or changing a medicine's dose.
  • Take a list of all your prescription and over-the-counter medications, vitamins and herbal products to each doctor visit.

Follow instructions carefully. If you're not getting enough of your blood-thinning medication, you may not adequately lower your risk for blood clots. But if you get too much, bleeding becomes more likely—and it can be serious.

  • Check your blood-thinning medicine when you get it home to make sure it's what you're expecting.
  • Carefully read your prescription label to make sure you're following all instructions. Don't take more or less than is prescribed for you.
  • Take each dose at the same time every day. Use a pillbox or other tool if you need reminders.
  • If you accidentally miss a dose, take it as soon as you remember. However, if you don't remember until the next day, contact your doctor and ask for instructions.
  • If your doctor orders blood tests, be sure to get them as recommended. These tests guide decisions about whether your blood thinner dose needs adjustment.
  • If your doctor calls to change your dose, write down the new instructions and read them back to him or her to make sure you understood correctly. Date the note so you don't mix it up with older instructions.

Take precautions. To lower bleeding risk, take steps to avoid cuts and other injuries.

  • Be especially careful when using knives and scissors.
  • Use an electric razor when shaving.
  • Choose a soft toothbrush and waxed dental floss for cleaning your teeth. Don't use toothpicks.
  • Always wear shoes or nonskid slippers.
  • Trim your toenails carefully. Don't cut corns or calluses yourself.
  • Wear gloves when handling sharp tools or doing yard work.
  • Avoid sports and other activities that can easily injure you or lead to a fall.

Watch your diet. Your diet and weight can affect how blood thinners work.

  • Don't start a weight-loss plan or make major changes to your diet without consulting your doctor.
  • Avoid alcohol.
  • Ask your doctor if you need to avoid or limit foods high in vitamin K. Some common sources of the vitamin include cranberries and cranberry juice; asparagus; broccoli; and green, leafy vegetables.

Know the signs of trouble. It's important to be aware of things that put you at risk for bleeding—and to recognize possible signs of bleeding.

  • Notify your doctor if you fall, receive a hard bump or have any type of accident. You could have internal bleeding without realizing it.
  • Seek medical help immediately if you have signs of bleeding: red or brown urine; bowel movements that are red or tarry; bleeding from the nose or gums that doesn't stop; brown or bright-red vomit; coughing up anything red; severe pain, such as a headache or stomachache; unusual bruising; a cut that doesn't stop bleeding; unusual menstrual bleeding; or dizziness or weakness.

Stay in contact with your doctor. If you have questions or concerns, don't hesitate to speak up. Be sure to touch base if:

  • You're pregnant or planning to become pregnant. Blood thinners may be dangerous for a developing baby.
  • You have diarrhea or vomiting that lasts more than one day or are unable to eat for any reason. Your blood thinner dose may need adjustment.

Reviewed 3/15/2022

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