Frequent INR testing can reduce future risks

Understanding your treatment

If you are on anticoagulation medication such as warfarin (Coumadin®), it is essential to understand why you are taking it. The primary role of anticoagulation medications is to prevent blood clots. Anticoagulation medications do not dissolve blood clots that have already formed, but they help to prevent them. Taking your medication as prescribed and having your blood tested are important factors in helping you stay healthier and live longer.

People on anticoagulation medication have medical conditions such as atrial fibrillation, thrombophlebitis, and others that increase the possibility of forming blood clots. Taking anticoagulation medication slows down how fast the blood clots, thereby preventing clots from forming in places that could lead to serious problems. The medication works by keeping certain substances in the blood from carrying out the natural processes that form blood clots.

Testing blood

People on these anticoagulation medications, which are often referred to as "blood thinners," must test their blood regularly to ensure that it is within a specific range. It is important to stay within this range, called the therapeutic range, in order to benefit from the medication and to prevent serious health complications, such as stroke or heart attack.

When a person on anticoagulation medication has a blood test, an INR (International Normalized Ratio) value is determined from the results. This INR value allows the doctor to determine how the medication is working and whether the dose you are taking is the right one for you. Adjusting the dosage of the medication helps keep the INR value of the blood in the optimal range to avoid possible complications (e.g., clotting or bleeding).

Benefits of frequent testing

INR values are typically checked at least once a month. However, more frequent testing is recommended in certain situations and can help to better monitor the effects of the medication on the blood. Testing more frequently using a portable self-testing coagulation monitor (e.g., CoaguChek) may help avoid complications related to anticoagulation medication.

Benefits of self-testing include:

  • Increased safety: If the medication is not working effectively, the blood will not be within the therapeutic range . Bleeding (also called hemorrhaging) may occur if the blood is not clotting at all, and a clot may form if it is clotting too much.
  • The comfort of knowing your INR value: If the value is within the optimal range, then the medication is working correctly. If it is outside of the optimal range, the medication is not working effectively, and you can contact your doctor to make the necessary arrangements to change the dosage.
  • More control over personal health: Knowing your INR level on a regular basis allows you to take charge of your health. You are involved with your treatment and can improve your quality of life and help prevent serious complications.
  • Convenience: Avoiding long line-ups in the medical laboratory or at the hospital makes checking your INR levels more convenient and saves time for patients and caregivers.

Frequent testing of the blood to check INR values allows you to better manage your own health. Knowing your INR value empowers you to take action when your INR value is outside of the optimal range. Other members of the healthcare team, including doctors and pharmacists, will assist in returning the INR value to the optimal range.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

How blood monitoring can affect your lifestyle

As many as 600,000 people in Canada are taking an anticoagulation medication called warfarin (Coumadin®). This medication helps slow blood clot formation in the body, preventing serious complications from some conditions. However, although warfarin is an effective medication, a person needs to have their blood tested throughout treatment to ensure the warfarin is being prescribed at the optimal strength. Close monitoring of blood clotting time is required to ensure safety of the person on this medication, as unwanted bleeding or clotting are potential concerns.

Effect of testing on lifestyle

While a person is on warfarin, blood tests are usually ordered by the doctor about every 4 to 6 weeks to check the person's INR (International Normalized Ratio). Most people go to a medical laboratory for this testing, although some attend specialized warfarin clinics in hospitals.

Naturally, time spent testing, waiting for results, and commuting can add up for both patients and their caregivers. Taking time off work is also a problem for busy working people. Employers are not always flexible enough to allow for adjustments based on clinic hours as it increases absenteeism and related cost. Since testing takes place regularly and for the full length of time that a person takes warfarin, this can become quite a chore.

In addition, extended traveling while on this medication may not be possible, as access to laboratories in other countries may be difficult and costly.

Simplifying testing

Purchasing a portable monitoring device and testing at home is a solution that more and more people are turning to. They may already be self-testing their blood sugar or blood pressure and so are familiar with the flexibility self-testing allows. Or they may simply find that they can't match their schedule to the hours of a lab or clinic.

When consumers who performed home blood monitoring with a portable coagulation monitor were asked what they liked about self-testing, many answered that they found it to be:

  • accurate
  • easy to use
  • an efficient alternative to laboratory testing

They also liked the flexibility and control that self-testing gives them.

For individuals on warfarin, self-testing allows them to quickly react to an INR level that is out of range by picking up the phone and informing their physician. Modifications to therapy can be accomplished swiftly.

Studies show that people who are able to keep their INR value within their optimal range 30% of the time significantly decrease their risk of serious complications. Although daily or weekly testing is not necessary for all people taking anticoagulants, it may be recommended by some physicians. People who use a portable coagulation monitor are more aware of their INR values. Being aware of your INR values through regular testing reduces the risk of serious complications.

Portable coagulation monitors are available in certified pharmacies throughout Canada.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

Quebec takes the lead in INR testing

Health care legislation recently passed in Quebec gives new authority to pharmacists and opens the door to new opportunities in patient care. The bill, called Bill 90, gives pharmacists the authority to adjust medication doses on the basis of test results. For some patients, this will mean less time commuting to and from their doctor. This is especially good news for people taking medications that require close monitoring, such as anticoagulants like warfarin (Coumadin®).

If you are currently taking warfarin, your doctor has probably told you that you will need to closely monitor your INR (International Normalized Ratio) on a regular basis. For many Canadians who use these medications, this means regular trips to the lab for blood tests, often including a wait for blood test results, possibly followed by trips or calls to the doctor's office for medication adjustments. Testing is important because it ensures that your blood is clotting neither too quickly, which raises your risk of clots, nor too slowly, which increases your risk of bleeding. If your INR falls out of a target range set by your doctor, the dosage of anticoagulation medication you are prescribed is adjusted so that the INR will return to the target range in order to reduce the risk of complications related to the medication.

Over 100,000 people in the province of Quebec use anticoagulation medications. And, until recently, like other Canadians who are prescribed this treatment, they had to be professionally monitored on a regular basis, along with the regular inconvenience that entailed. With the new legislation in place, Quebecers will be able to monitor their own INR and get their treatment adjusted by the pharmacist where necessary, without delay or inconvenience. Pharmacists will play a major role in improving a person's quality of life through their ability to monitor patients and decrease the waiting time in laboratories or doctor's offices.

In Quebec, the first step is that the patient needs to get a prescription from a doctor for a self-testing coagulation monitor. Once a patient receives this prescription, they are educated by a specially-trained pharmacist on how to use the monitor and the test strip. They also receive follow-up by the pharmacist to ensure that they continue to perform the monitoring correctly. The patient can either do self-testing at home or have it done in pharmacy.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

Do cardiologists support self-testing?

If you are on anticoagulation medication, then you are familiar with the time-consuming routine of trekking to the lab to test your INR level, and then, if the results require, scheduling a trip to the doctor to adjust your dosage.

Fortunately, there are new alternatives for people taking anticoagulation medications such as warfarin. Self-testing devices are now available at many pharmacies. These home testing devices provide greater convenience and allow people on warfarin and other anticoagulation medications to become more in tune with changes to their INR levels. But do cardiologists - the experts in the field - think people should use them?

Self-testing may not be the solution for everyone, but doctors agree that it can allow some patients to play a more active, involved role in their care. "The most important factor is an educated, responsible patient who will follow instructions closely," says Dr. C. Russell Mao, Chief Cardiology Fellow at the University of British Columbia.

"They also need to have a good relationship with their physician so that any questions the patient may have will be addressed promptly by the physician," adds Dr. Mao

Self-testing can particularly decrease inconvenience for patients who may need more frequent INR testing. "Any changes in medications or diet change the effects of warfarin," says Dr. Mao. "Therefore, you will need to check your INR more often initially. Also, any disease states such as infections, liver problems, or even high thyroid states can increase the potency of warfarin. Thus the INR needs to be checked more frequently."

Dr. Mao says some patients, such as people with diabetes who are used to testing their blood glucose levels at home, are particularly good candidates for INR self-testing.

"The first step is to talk with your doctor to see if they agree that this is a good option for you and that they will be available to answer any questions you have, including about changes to your warfarin doses according to your INR levels. Prior to starting self-testing, you will also need to be trained on how to use the monitor and how to interpret your results.

"If all of this is in place, then self-testing would be a good option for you."

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: