Adult Medication

Brand Names: Canada


What is this drug used for?

  • It is used to thin the blood so that clots will not form.
  • It is used to treat blood clots.

What do I need to tell my doctor BEFORE I take this drug?

  • If you have an allergy to acenocoumarol or any other part of this drug.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: Blood vessel problems like aneurysm or dissecting aorta; bleeding problems; bleeding in the brain; active ulcer; bleeding of the stomach, bowel, urinary tract, genitals, or respiratory tract; blood problems; heart problems like pericarditis or heart valve infection; kidney disease; liver disease; low platelet count; recent surgery, including surgery of the eye or brain; very high blood pressure; low vitamin C levels; arthritis; mental problems; or you drink too much alcohol.
  • If you know that you will not take the drug as you have been told.
  • If you are pregnant or may be pregnant. Do not take this drug if you are pregnant.
  • If you will be getting spinal anesthesia or a spinal treatment.
  • If you are taking any of these drugs: Aspirin, diflunisal, para-aminosalicylic acid (PAS), phenylbutazone, salicylic acid, or sulfinpyrazone.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

  • Tell dentists, surgeons, and other doctors that you use this drug.
  • Tell your doctor you take this drug before you get any drug given as a shot into the muscle.
  • Wear disease medical alert ID (identification).
  • Use care to prevent injury and avoid falls or crashes.
  • Avoid actions or sports that may raise the chance of injury or bleeding.
  • If you fall or hurt yourself, or if you hit your head, call your doctor right away. Talk with your doctor even if you feel fine.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
  • Take good care of your teeth. See a dentist often.
  • Talk with your doctor before using products that have aspirin, blood thinners, garlic, ginseng, ginkgo, ibuprofen or like products, pain drugs, or vitamin E.
  • Talk with your doctor before taking multivitamins, natural products, and diet aids. These may have vitamin K in them.
  • Talk with your doctor about the amount of vitamin K in your diet. Vitamin K may change how this drug works. You do not have to avoid all foods with vitamin K. However, you will need to keep the amount of foods with vitamin K in your diet about the same from day to day. Many foods have vitamin K in them. This includes some green, leafy vegetables; broccoli; liver; and certain vegetable oils. Get a list of foods that have vitamin K in them from your doctor. Do not make big changes in your normal diet without talking with your doctor.
  • Follow the diet and workout plan that your doctor told you about.
  • Avoid drinking alcohol.
  • If you are 65 or older, use this drug with care. You could have more side effects.
  • Use birth control that you can trust to prevent pregnancy while taking this drug.
  • This drug may cause harm to the unborn baby if you take it while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of bleeding like throwing up blood or throw up that looks like coffee grounds; coughing up blood; blood in the urine; black, red, or tarry stools; bleeding from the gums; vaginal bleeding that is not normal; bruises without a reason or that get bigger; or any bleeding that is very bad or that you cannot stop.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Very heavy periods (menstrual bleeding).
  • Very bad dizziness or passing out.
  • Feeling very tired or weak.
  • Change in thinking clearly and with logic.
  • Very bad headache.
  • Change in strength on 1 side is greater than the other, trouble speaking or thinking, change in balance, or blurred eyesight.
  • Very bad belly pain.
  • Very bad back pain.
  • Change in skin color to black or purple.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if you have any side effects that bother you or do not go away.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
  • Use this drug exactly as you have been told, even if you feel well. This is important for the drug to work right and to lower the risk of bleeding.
  • Take this drug at the same time of day.
  • To gain the most benefit, do not miss doses.
  • Take with or without food.
  • Do not stop taking this drug all of a sudden without calling your doctor. You may have a greater risk of side effects. If you need to stop this drug, you will want to slowly stop it as ordered by your doctor.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

How do I store and/or throw out this drug?

  • Store at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Check with your pharmacist about how to throw out unused drugs.

General drug facts

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else’s drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Last Reviewed Date



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©2015 Memorial Sloan Kettering Cancer Center - Generated on November 30, 2015