Coumadin, also known by its generic name warfarin, is an anticoagulant medication used to prevent blood clotting. It belongs to a class of drugs called vitamin K antagonists. Coumadin is primarily prescribed to patients at risk of developing blood clots, such as those with atrial fibrillation (an irregular heartbeat), deep vein thrombosis (blood clot in the legs), pulmonary embolism (blood clot in the lungs), or those who have undergone certain surgical procedures.

Drug Name: Coumadin

Active Ingredient: Warfarin

Coumadin tablets



Form: Tablet

Type: Generic

Prescription Required: Rx

Availability: In Stock

Coumadin works by inhibiting the production of vitamin K-dependent clotting factors in the liver, which are necessary for blood clot formation. By reducing the production of these clotting factors, Warfarin helps prevent the formation of blood clots.

The dosage of Coumadin varies depending on the individual's specific condition, and it requires careful monitoring to ensure the blood is maintained at the desired level of anticoagulation. Regular blood tests, such as the international normalized ratio (INR) test, are performed to measure the clotting ability of the blood and adjust the dosage accordingly.

How to use

Here are some general guidelines for using Coumadin:

  • Timing: Take medicine at the same time each day to maintain a consistent level of the medication in your body. It is often recommended to take it in the evening to minimize the impact of any potential bleeding episodes that may occur.
  • Interactions: Inform your doctor about all the medications you are taking, including prescription drugs, over-the-counter medications, vitamins, and herbal supplements. Warfarin can interact with certain medications, foods, and supplements, potentially affecting its effectiveness or increasing the risk of bleeding.
  • Diet: Coumadin interacts with vitamin K, so it is important to maintain a consistent intake of foods containing vitamin K. Avoid making significant changes to your diet, especially in foods rich in vitamin K (e.g., leafy green vegetables like spinach, kale, and broccoli).
  • Safety measures: As Coumadin increases the risk of bleeding, it is important to take precautions to minimize potential injuries. Use a soft-bristle toothbrush and waxed dental floss to prevent gum bleeding. Avoid activities that may increase the risk of injury or bleeding, such as contact sports or using sharp objects without necessary precautions.
  • Medication management: Store drug at room temperature, away from moisture and heat. Keep it out of reach of children and dispose of any expired or unused medication properly.


The dosage of Coumadin varies depending on individual factors such as the condition being treated, the patient's response to the medication, and regular blood tests monitoring the clotting ability of the blood, specifically the international normalized ratio (INR). The following are some general guidelines dosage:

  1. INR Monitoring: Regular blood tests are conducted to measure the INR, which indicates the clotting ability of your blood. The INR helps determine if the dosage of Coumadin needs adjustment. The target INR range may vary depending on the underlying condition being treated. Typically, for most conditions, an INR of 2.0 to 3.0 is considered therapeutic.
  2. Interaction Management: Coumadin can interact with other medications, both prescription and over-the-counter, as well as certain foods and supplements.

Side effects

Coumadin can have side effects, and it is important to be aware of them while using this medication. Not everyone will experience side effects, and their severity can vary from person to person. Some common side effects include:

  1. Bleeding: Warfarin is an anticoagulant, meaning it helps prevent blood clotting. However, it can also increase the risk of bleeding. This can manifest as nosebleeds, bleeding gums, easy bruising, prolonged bleeding from cuts, blood in urine or stools, or unusual heavy menstrual bleeding. In rare cases, severe bleeding or hemorrhage can occur, which requires immediate medical attention.
  2. Skin changes: Some individuals may develop skin-related side effects, such as rash, itching, or purple toes syndrome (characterized by a bluish or purplish discoloration of the toes).
  3. Hair loss: In rare cases, Coumadin use has been associated with hair loss. However, this side effect is uncommon.
  4. Digestive system issues: Drug can cause digestive system-related side effects like nausea, vomiting, diarrhea, and stomach pain. These symptoms are generally mild and resolve on their own.
  5. Allergic reactions: In rare cases, allergic reactions to Coumadin can occur. Signs of an allergic reaction may include hives, itching, swelling (particularly of the face, throat, or tongue), severe dizziness, and difficulty breathing. Seek immediate medical attention if you experience any of these symptoms.
  6. Purple, painful, or cold limbs: Rarely, Coumadin can cause a condition known as warfarin-induced skin necrosis. It typically affects fatty tissues and can cause purple discoloration, pain, and a cold sensation in the affected area.

It is important to note that Coumadin can interact with other medications, foods, and supplements, which may increase the risk of side effects or alter its effectiveness.

If you experience any concerning or severe side effects while taking Warfarin, it is essential to seek medical attention immediately.


When it comes to storing Coumadin, it is important to follow proper storage guidelines to maintain its effectiveness and safety. Here are some recommendations for storing:

  1. Temperature: Store medicine at room temperature, typically between 20°C to 25°C (68°F to 77°F). Avoid exposing the medication to excessive heat or cold. Do not refrigerate or freeze Coumadin.
  2. Moisture: Keep tablets away from excessive moisture. Store it in a dry place, such as a closed container or the original packaging provided by the manufacturer. Moisture can potentially affect the stability of the medication.
  3. Protection from light: Protect Coumadin from direct sunlight or intense artificial light. Exposure to light can degrade the medication and reduce its potency. Keep the medication in a dark place, such as a cabinet or drawer.
  4. Childproof container: Store Coumadin in a childproof container or a secure location out of the reach of children. This helps prevent accidental ingestion by children, as Coumadin can be harmful if taken by someone who is not prescribed the medication.
  5. Medication disposal: Dispose of any expired or unused Coumadin properly. Do not keep medicament beyond its expiration date, as its effectiveness cannot be guaranteed. Follow local guidelines or consult a pharmacist to learn about proper medication disposal methods.

Always check the specific storage instructions provided with your Coumadin prescription, as there may be additional considerations or recommendations.

Remember, proper storage helps ensure the integrity and effectiveness of the medication, promoting its safe and optimal use.


An overdose of Warfarin can have serious consequences and should be treated as a medical emergency. If you suspect an overdose or have taken more than the prescribed dosage of Coumadin, take the following steps:

  1. Seek immediate medical help: Contact your local emergency services or go to the nearest emergency room right away. Inform them about the situation and that you suspect an overdose of Coumadin.
  2. Do not induce vomiting: Do not attempt to induce vomiting. Vomiting may increase the risk of further complications.
  3. Be prepared with information: Provide as much information as possible to the medical professionals regarding the quantity of Coumadin taken, the time of ingestion, and any other relevant details. This information will assist them in determining the appropriate course of treatment.
  4. Medical treatment: In cases of Coumadin overdose, treatment typically involves measures to reduce the effects of the medication and control bleeding, if present. This may include administering vitamin K, fresh frozen plasma, or other clotting factors to counteract the anticoagulant effects. The specific treatment approach will depend on the severity of the overdose and the individual's condition.

It is important to remember that an overdose of Warfarin can increase the risk of bleeding, which can be life-threatening. Prompt medical intervention is crucial to manage the effects of the overdose and prevent further complications.

If you have any concerns about your Coumadin dosage or suspect an overdose, seek immediate medical attention. It is always better to err on the side of caution when it comes to medication safety.

Missed Doses

If you miss a dose of Coumadin, it is important to take the necessary steps to manage the situation. Here are some guidelines to follow:

  1. Take the missed dose as soon as you remember: If you realize you missed a dose and it is still within a reasonable timeframe, take the missed dose as soon as possible. However, if it is close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not double up on doses to make up for a missed one.
  2. Monitor your INR: If you have missed a dose, it is important to monitor your international normalized ratio (INR) more closely.
  3. Prevent future missed doses: To avoid missed doses in the future, it is helpful to establish a routine for taking Coumadin. Consider setting reminders or alarms to prompt you to take your medication at the same time each day. Additionally, keeping a supply of Coumadin accessible, such as in a pill organizer, can help ensure you have easy access to your medication.

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