Since life-threatening problems can occur if you take too little or too much Coumadin, dosing must be individualized for each person. Starting or stopping a new medication and changes in the diet are factors that may affect dosing requirements. Frequent adjustments are often necessary, as a dosage that works well today may not be appropriate next week.
The dose of Coumadin® (warfarin sodium) your healthcare provider recommends will vary, depending on how you respond to the medication (this is monitored using regular blood tests). As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
Coumadin is not dosed like most other medications. While it can be a life-saving drug, unfortunately, the side effects can be life-threatening. Taking too little increases your risk for blood clots and strokes, and taking too much increases your risk for dangerous internal bleeding. Even tiny dosing changes can have a large effect. In addition, a dose that is safe and effective for one person may be much too high or too low for another person.
Therefore, dosing for Coumadin must be individualized. It is not necessarily related to body weight, and many factors affect the dose. Keep in mind that an amount that works well today may not be appropriate next week. Sometimes, frequent adjustments are necessary, although ideally, most people will achieve a somewhat steady dose.