INR Testing Machines: How to Use Them at Home

What Are INR Machines?

An INR machine is a portable meter that works on batteries and measures the person’s response to warfarin. It also has a screen where you can see the results and a small opening to insert the test strip. You can use it by taking a tiny bit of your blood with a small needle and placing it on the test strip. The machine measures how much time it takes for the test blood to clot and displays the results on the screen. The calculation is based on the International Normalized Ratio (INR), which doctors use to determine if you’re receiving the correct dose of warfarin.

Who Should Use INR Machines?

Patients who can’t go to the lab often, travel frequently, have trouble leaving their homes, or like to be more independent can choose in-home testing. Whatever your reason for switching to home testing, the most important thing is to stick to it. But some blood disorders like antiphospholipid syndrome can interfere with the results, so it’s best to consult with your doctor before you look into buying INR testing machines.

Tips for Using an INR Machine at Home

Just like you can test your blood sugar levels at home if you have diabetes, you can also test your INR for coagulation. After you’ve consulted with your doctor and they have approved home testing, you are good to go. You should be able to know what results to expect, what is the average INR value for you, and you should recognise any potential dangers. Always read the instructions on the back of the box to make sure you’re doing everything right. Before taking the blood, make sure that:

• Your fingers are warm enough for the blood to flow;
• Clean the finger and dry it completely;
• Don’t squeeze the finger to get the blood out;
• If you can’t do it, try on another finger.

How Often Should You Use it?

Follow your doctor’s instructions on how often you should take the test. It’s usually in the time frame between 1-4 weeks. Before changing any of your drugs that could change your warfarin dose or monitoring schedule, speak with your health care provider. Also, let your doctor know if you changed your diet, as some foods, such as leafy greens and some herbal products, can impact how you respond to warfarin.

When to Contact Your Doctor?

Doing your own tests at home is convenient, saves time and money and spares you from driving through heavy traffic to get to the lab. If you have an INR test meter, you can do the test whenever you like without leaving the comfort of your own home. However, you should be aware that there are possible risks when using this machine at home. Some symptoms will tell you that you have a problem with warfarin. Some of them are:

• Nosebleeds;
• Bleeding you can’t stop;
• Blood in urine and stool;
• Vomiting blood;
• Leg pain;
• Confusion;
• Difficulty with speaking;
• Headache;
• Stomach pain;
• Difficulty breathing;
• Dizziness and loss of coordination.

If you experience any of these symptoms, contact your doctor immediately. They’ll be able to stop the bleeding or relieve the pain and symptoms. You should know your appropriate INR range, so if you get results out of that range, it doesn’t matter if they’re lower or higher, call your doctor. They will instruct you on what to do next and probably send you to the lab to do another test. This way, they can confirm if the results from the INR testing machines are reliable.

What Affects the INR Results?

If you experience any kind of illness, even a simple common cold, there may be changes in your results. Also, changing your food habits, or eating too many leafy greens such as kale, spinach, cabbage and parsley, may alter the results. Another factor is the proper care and maintenance of the machine itself. If you have faulty test strips or don’t store and clean the meter as you should, you might get incorrect results. Other factors are:

• Using too much or too little blood;
• Waiting too long to test;
• Squeezing the finger;
• Moving the machine while it’s testing.

Depending on what type of machine you use, the results may be affected by certain antibiotics you drink, medical conditions such as anemia or infections, and the overall environmental factors like temperature and humidity.

Benefits of In-Home Testing

While doctors can use regular in-office testing to monitor INR levels successfully and securely, INR testing at home has enormous benefits. While self-testing may not be appropriate for every patient, it may be helpful for many. Measuring anywhere, at any time, can provide you with more freedom. If you’re on a vitamin K antagonist like warfarin and want to check your INR levels, you can do so at any time. You can start filling your calendar with things you want to do instead of appointments to go to and get blood out.

You can take a more active role in your treatment, providing you with the confidence and assurance to keep your vitamin K antagonist therapy under control. You can measure your INR values if you are concerned about whether you are in the therapeutic range or not. Without having to wait days for lab results, your doctor will be able to make any necessary changes in the therapy right away. Every person can learn how to do this at home and enjoy these benefits.