Warfarin(Coumadin) decreases the body’s production of vitamin K, which stops the production of a large variety of clotting factors and prevents blood clot formation. It used to treat conditions such as atrial fibrillation, deep venous thrombosis, pulmonary embolisms, and others.
Take this medication by mouth with water, it can be taken with or without food.
Take this medication at the same time every day.
Take it exactly as directed, do not take it more than directed.
Do not stop taking this medication suddenly or without consulting with your healthcare provider. Stopping this medication suddenly increases your chance of developing a blood clot. Ensure that your refill is ready and in your possession before running out of the medicine.
If your doctor tells you over the phone to change the dose, be sure to write down the dose along with the date of the new instructions. Read the dose and instructions back to the doctor to ensure accuracy. If you are informed that you should stop taking the medicine until your upcoming blood test, be sure that after the blood test you contact your doctor to find out when to continue the medication regimen.
Contact a healthcare provider if you develop signs and symptoms of bleeding such as: Black, tarry or bloody stools, dark brown or red urine, spitting up blood or coffee ground colored material, red spots on the skin surface, bruising or bleeding of the eyes, nose, gums, or skin.
Alcoholism, anemia, blood disorders, diabetes, cancer, heart diseases, high blood pressure, history of gastrointestinal bleeding, history of brain injuries or strokes, brain diseases, protein C deficiency, protein S deficiency, dementia, psychosis, any recent injuries, recent surgery, planned future surgeries, history of allergic reactions, pregnancy, breastfeeding, trying to become pregnant.
Allergic reactionx(hives, itching, rashes, swelling of the face or mouth), trouble breathing, back pain, chills, dizziness, fever, vaginal bleeding, heavy menstrual bleeding, toes that are painful, blue or purple in color, painful or prolonged erection, excessive fatigue, unusually weak or tired, yellowing of the skin or eyes, stomach pain, signs and symptoms of bleeding such as: Black, tarry or bloody stools, dark brown or red urine, spitting up blood or coffee ground colored material, red spots on the skin surface, bruising or bleeding of the eyes, nose, gums, or skin.
Hair loss, diarrhea.
The dose for warfarin is unique for each patient and is individualized based on the patient’s INR. The target INR is typically between 2 and 3.
Between 2mg and 5mg by mouth or intravenously as a starting dose. The dose is then titrated based on the INR. The usual maintenance dose is between 2mg and 10mg.
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By: Evan Redmond, Pharm.D.