Coumadin is a life-saving medication when used and monitored properly. Because so many new medications and some foods affect the action of Coumadin, SETMA has established a special clinic where you can get your prothrombin time (Protime) checked easily with immediate results. This saves you time and makes sure you're getting the right dose of medication.
You will also be given educational materials which will tell you about foods you should not eat and the signs and symptoms of dangerous changes in your Protime. Always keep your appointments to have your Protime checked. If you have any bleeding or easy bruising, do not take your next dose of Coumadin and call your healthcare provider immediately. If you are taking Coumadin, do not take aspirin or aspirin-containing medications. The staff of SETMA's Coumadin Clinic maintains a continuous, computer-based, record of your Protimes.
Facts about Coumadin
Coumadin is the brand name for Warfarin sodium, a very important but potentially dangerous drug. Thousands have used it, safely and effectively, to prevent strokes, heart attacks, blood clots in the legs and lungs and other disorders. When an artery or view is injured, the blood normal stops flowing after a clot is formed. The clot is the result of a complex series of steps, which include platelets, which are small particles in the blood, and a number of clotting factors, which are proteins in the blood.
Coumadin should be taken with great caution and care. Coumadin can be very safe, if the person taking Coumadin understands:
- Why they are taking it?
- What it is doing to them?
- How to monitor it effectively?
Coumadin was discovered when farmers notice that cows that ate a certain kind of clover were dying for an unknown reason. When analyzed, it was found that a chemical in the flower of the clover caused the blood not to clot. This substance was called warfarin. A chemist thought, If warfarin will kill cows when ingested in excessive amounts, why cant we mix warfarin in pills which rats will eat and use it as a rat poison? This was the first use of warfarin. Even today warfarin is used as an active ingredient in rat poison.
Other scientists conjectured that if excessive amounts of warfarin would completely prevent the blood from clotting, smaller amounts would only slow the clotting capacity of blood. If that were the case, then warfarin could be used clinically in conditions where there was either a tendency for the blood to clot too quickly, called hyperviscosity syndromes, or in conditions where it was important to slow the clotting of blood, such as those mentioned above.
After adequate study, warfarin was found to slow the production of clotting proteins that are made in the liver. It does so by inhibiting the action of Vitamin K, which promotes the formation of some of the clotting proteins. In other words, Coumadin (warfarin) "thins the blood," preventing the formation of clots in the blood system.
Conditions Which Benefit from Coumadin
There are several conditions in which Coumadin is used, although not everyone with these conditions has to be on this medication. The list below does not include all possible conditions for which warfarin can be used, but it does include most of the important ones:
- Deep Venous Thromboses -- Clots in the legs or other parts of the body, which have the potential to break loose and go to the lungs causing potentially deadly "Pulmonary Emboli."
- Artificial heart valves -- Can promote abnormal clotting in the blood.
- Atrial Fibrillation - A condition of irregular heart rhythm, which can promote abnormal clotting in the heart itself. These clots can be dislodged and travel to other parts of the body. If they lodge in an artery to the brain, they can cause a stroke.
- Transient Ischemic Attacks (TIA) - A pre-stroke condition in which there is a temporary dysfunction of part of the brain. A TIA is brief, but frightening. Coumadin can prevent a TIA from becoming a stroke.
- Heart Attacks -- Some people who have had heart attacks will benefit from Coumadin therapy.
- Some people with blocked arteries.
- After knee or hip surgery, a short course of Coumadin can often prevent DVTs from developing.
- Some people with certain types of abnormal clotting disorders will benefit from Coumadin.
The length of time that a person is on Coumadin depends on the reason why that person needs to have clot prevention. Blood clots in the legs are treated for:
- Six months for a one-time episode,
- One year if it happens again.
- A third blood clot in legs means a lifetime of Coumadin therapy.
Atrial fibrillation is another reason why one would be on Coumadin for life. Those with heart disease and strokes can also be on Coumadin for as long as it is safe to do so.
How Does Your Healthcare Provider Gauge Your Coumadin Dose?
The INR (International Normalized Ratio) is the best way to monitor the effects of Coumadin on the body. It is the test used to measure how "thin" ones blood is. The INR is currently recommended as the value to adjust the dose of Coumadin. The INR expresses the speed of blood clotting and corrects for any inconsistencies in the control samples.
Although many Coumadin patients are familiar with the PT (Prothrombin Time), it has fallen out of favor for monitoring Coumadin therapy. The INR is checked at your health care providers office, periodically depending on how stable your Coumadin level is.
Once an INR is stable monthly monitoring is appropriate, however when starting on Coumadin or during illness or while taking new medications, more frequent monitoring is necessary, usually once weekly until stable. Always know you when you are to have your next blood test and your current dose.
How thin ones blood should be is determined by the condition of that person. For most conditions, the INR is optimally kept in the range of 2.0-3.0. For other conditions, the desirable range is higher, around 2.5-3.5. This is a goal that has to be set by your provider, depending on a number of factors about your condition.
The dose of Coumadin that a person is taking daily depends on the INR, and the condition that is being treated. Several factors influence how thin the blood is in each person. Diet, medications and weight are a few of those factors. Coumadin comes in multiple doses from 1mg up to 10 mg.
Food and Coumadin
Diet is an important factor due to the amount of Vitamin K that can be obtained through foods that we eat. Such foods include kale, spinach, and many green leafy vegetables. Also, broccoli, cauliflower, Brussels sprouts and green tea are high in Vitamin K. Because these foods are high in Vitamin K does not mean that they have to be avoided. You may eat these foods; the key is to be consistent and regular with these foods in your diet. Realize that significant changes in your diet can cause changes in the Coumadin's potency.
Medical conditions such as liver problems can influence Coumadin levels. Since Coumadin works in the liver to suppress blood clotting, those with alcoholism and cirrhosis of the liver would not be able to take Coumadin.
Anyone taking Coumadin should be very careful overindulging with alcohol. Also those taking medications that may affect the liver such as anti-fungal agents, cholesterol medications and certain antibiotics will affect the INR.
If you are on Coumadin, be sure to tell anyone who is prescribing you medication that you are on Coumadin, and ask whether there are any effects on its metabolism. Always double-check this with your pharmacist. Don't take over-the-counter medicines without checking with your pharmacist and your healthcare provider.
It is recommended that you take Coumadin in the evening. It does not really matter when it is taken, however, by taking it in the evening allows time for the providers office to call you back with your INR result, if any dosage adjustment is needed.
Coumadin should be taken with a strict schedule. One must make an extra effort not to deviate from the medication schedule. Every once in a while, however, it is not unusual to miss a dose of medication for one reason or another. If you miss your dose of Coumadin and it has been within 12 hours of your scheduled dose, go ahead and take it. Otherwise, skip the dose, but let your provider know about the missed dose.
Patients taking Coumadin have to follow lots of rules. There may be alternative medications, and your healthcare provider knows about those medications. For now, Coumadin has an important place in the treatment of certain medical conditions, and trials to this point have not found suitable alternatives in many situations.
Although aspirin is a blood thinner, it may not be potent enough for many circumstances. Other agents like dipyridamole (Persantine), ticlodipine (Ticlid) and others do not do enough in many cases (although they may be preferred over Coumadin in other cases).
Guidelines To Make Taking Coumadin Safer
Coumadin is a very effective and necessary medication when used correctly. Follow these reminders to be safe:
- Always know when you are to have your next blood test and what your current dose of Coumadin is.
- Remind anyone who prescribes medicine for you that you are on warfarin (there are important interactions with a number of other medications).
- Report any unusual bleeding (it doesn't need to be a lot, it is simply important that it is occurring "for no good reason").
- Get your blood tested as directed!
- Realize that significant changes in your diet can cause changes in the Coumadin's potency.
- Call your physician with questions earlier rather than later.
- Consider obtaining a "Medic Alert" or similar bracelet stating that you are on Warfarin.
To get the best and safest result from coumadin have your treatment management by a clinic design especially for coumadin management. SETMA's Coumadin Clinic is one such clinic. |
