Lena Welch was diagnosed with a pulmonary embolism and factor V Leiden in 2008. She has participated in support groups for each condition.
Coumadin (warfarin) has to be monitored on a routine basis to ensure that the patient is receiving the correct dosage. Home monitoring is one of a few options for patients to consider while they are using warfarin for anticoagulation therapy. They will need to have blood checks done frequently, starting daily, but as the patient's blood levels stabilize, the checks may become further apart.
These checks are done to measure international normalized ratio (INR), a number that represents the amount of time your blood takes to clot (prothrombin time, or PT).
There are currently three different methods for checking INR:
- The traditional way: The patient goes to his or her doctor's office or to an anticoagulation clinic. Blood is drawn from a vein and sent to a lab. Results can take anywhere from 1-2 hours to 1-2 days to return since some places use third-party labs for this test. Once the results are received, the patient will be notified of their INR and adjusted warfarin dose.
- The physician's office using a point-of-care machine: The patient goes to his or her doctor's office or anticoagulation clinic. A fingerstick is done, and a drop of blood is placed on a small machine. In a few minutes, the machine shows the INR and the dose is adjusted.
- Self-testing: A patient purchases a point-of-care machine for home use. The patient performs his or her own fingerstick and blood test. The INR is shown in a few minutes. The patient reports the INR to his or her doctor for dose adjustments. In European countries, it is becoming increasingly common for patients to self-adjust warfarin dosage. At this time, this is highly uncommon in the US and Canada. It is not recommended to change your own dosages—always consult your doctor first.
This article will provide you with some great information about the pros and cons of self-testing and where to purchase the necessary machine.
Disclaimer: Please speak with your doctor about the best INR monitoring option for you. Note that I am not a medical professional. I was diagnosed with a pulmonary embolism and factor V Leiden in 2008, and I have attended support groups and researched the topic extensively.
Advantages of Testing at Home
While doctors and anticoagulation clinics provide excellent care, testing at home can really benefit some patients.
- It is more convenient. There are no trips to the doctor for blood work. This saves you gas and driving time. For patients who are driving long distances to see a doctor, or who do not have transportation, this will be a huge help. If a warfarin user travels a lot or works an unusual schedule, INR scheduling can be very problematic. Home-testing can be done anytime and anywhere.
- Patients often feel empowered. This is a great feeling for many people who feel tethered by their medication regimen. It allows the patient to more easily track INR when there are medication, diet, or other changes rather than trying to schedule an appointment when something unexpected happens.
- You only need a drop of blood. Point-of-care monitors only use a small drop of blood from a fingerstick. This will be a large relief to anyone who has problems with IV blood draws.
Disadvantages of Testing at Home
- Home INR machines do not work well for people with APS (antiphospholipid syndrome). The antiphospholipid antibodies can disrupt the phospholipid in the prothrombin time (PT) reagent and cause an incorrect INR reading. If you have APS and want to use a home INR machine, please read the literature at the APS Foundation and discuss with your physician. Occasionally, home testing can be done after carefully comparing home INR readings with venous blood draw readings.
- It may not work well for patients with INRs over 4.0. The National Blood Clot Alliance notes that this is a problem for both venous blood draws and point-of-care machines.
Is Testing INR at Home Reliable?
A 2008 study found that home-testing is as reliable as testing done by a doctor. This study mirrors the results of numerous other studies that show testing at home improves warfarin management by more quickly identifying patients who are out of INR range and engaging patients in their own care.
You may be a good candidate for home INR testing if:
- You are compliant with your anticoagulation therapy.
- You have the manual dexterity to do the fingerstick and get the blood drop on the test strip or you have someone to help you with this.
- Your doctor or anticoagulation clinic is open to home INR testing and will work with you to design an effective home INR treatment plan
- You meet your insurance provider's coverage requirements for home INR testing (varies by company) or can pay out of pocket for testing equipment and supplies.
Many insurance plans, including Medicaid and Medicare, will cover the cost of home INR testing for some (but not all) conditions that require anticoagulation therapy. Speak with your insurance provider for information about coverage. Many machine distributors may also be able to help you understand your insurance coverage and options. Take a look at distributor sites below for assistance with insurance questions. According to ClotCare, home INR machines cost $1,000-$2,000 and test strips are around $12 each without insurance.
Manufacturers and Suppliers
- PTINR.com | Home INR Monitoring
- mdINR - Manage Your Coumadin Patients | INR Home Testing
With mdINR, doctors can manage their coumadin clients and patients can take charge of their inr testing.
- Philips Home INR
Coumadin level monitoring for Doctors and Patients taking Coumadin or other generic warfarin anticoagulation medication.
- CoaguChek - Know your INR value
A PT/INR tester for home use, the CoaguChek® gives accurate anticoagulation results in less than a minute.
What Are the Next Steps?
If you are interested in home INR management, consult your doctor that currently manages your anticoagulation. Your doctor will still be highly involved in your care, so it is vital that he or she has a say in your decision to switch to home care.
The next step will be to get a prescription from your doctor and to speak with your insurance provider. I recommend checking out the sites that I have provided as well as going to the Daily Strength Pulmonary Embolism Support Group online to ask questions because many members there have purchased and used a home INR machine. They can recommend suppliers and give you reviews of the customer service they have received.
Once you have received your home care machine, please share your experiences in the comments section below. I look forward to hearing from everyone!
- Aetna's Policy on Prothrombin Time (INR) Home Testing Devices
- INR Self-Testing. Patient Education Blog. Clot Connect
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
FOO YONG TAI WILLIAM on May 13, 2019:
need.to more information to prevent the cause before too late
HADIR ATTIA on November 30, 2017:
Hallo , i had 2 blood clots in both my legs recently, and the doctors are having hard time to satle my INR and the Coumadin dose . im living in Canada , so how can i get this machine .
Barb Johnson from Alaska's Kenai Peninsula on April 24, 2015:
Thanks for the thorough information Lena! Have been considering a device for my Dad. He tires of the back and forth office visits.
Lena Welch (author) from USA on April 15, 2015:
Hi Ross, try my manufacturer links. Typically you will order the machine straight from them. I know ptinr is one company that is distributing them and I think there are others. Get on a search engine and search for home INR testing.
Ross on April 15, 2015:
I've been on Coumadin for 20 years and have just received a prescription for the INR Meter. I am not able to find a medical supply or pharmacy that carry the meter.
Lena Welch (author) from USA on July 10, 2014:
I don't know the differences between the machines. I think that my doctor used a Coagucheck when I was on warfarin. That was many years ago now so I don't know what his office uses now. Some are rentals and others are to purchase. You would want to figure that out. I used to hear good things about Alere's ptinr.com site and customer service.
Victor on July 10, 2014:
I have undergone redo Aortic valve replacement and Mitral Valve repair. I have been on warfarin for the last 13 years. Its always a pain in the neck going to lab and getting PT INR done. I am planning to purchase home test kit but not very sure which is the best instrument available. I would appreciate if anyone could let give some tips and suggestion. I am from New Delhi, India and the insurance thing is not available here. What is the most cost effective and good PT INR kit for home.
Lena Welch (author) from USA on June 20, 2014:
That wasn't due to the product recall was it? I know that Alere has had a recall on some of the models.
Jim Musgrove on June 20, 2014:
I have been home testing for over 3 years now using Alere monitor and all of a sudden they want the monitor back that I paid over 3,000.00 for. They say it was on loan. Please beware of Alere and any other companies when you start home testing. I don't know how other companies operate but Alere sells their equipment and then come back later and say that you only paid for a service, not the meter and supplies that can be purchased far cheaper on ebay. Beware of the scams like Alere operates.
Tam Nguyen on May 08, 2014:
I have been on Warfarin care for 13 years now. Two year ago I decided to self-manage the INR with a portable Coagucheck XS. I find this little equipment help me to manage Warfarin doses very well. I have also learned how to adjust the doses from previous INR dosing instruction records from the pathology and online Warfarin dosing advice and to understand foods, vegetables, alcohol, drugs that interfere with the Warfarin.
I have 18 months consecutive INR within the target range and only 2 times were out of range. Once was 4.1 because I eat too much mango. Once was 5.8 because I took Prednisone and I quickly brought the INR back to normal in a couple of days. To be able to manage the INR by yourself, you will need:
The equipment and test strip of course.
Learn how to adjust the doses based on the rise and fall of the INR.
Learn the delta of INR between tests using the equipment and from pathology at least 5 times.
Maintain a schedule of test records for your reference in dose changing.
Visit the pathology for INR test 1 every 2 months or whenever the INR goes out of the range significantly. This is to confirm the INR. Don’t just to rely on the machine alone.
Consult your GP for significant changes in INR that you are not confident with self-dosing adjustment.
Lena Welch (author) from USA on January 08, 2014:
That is up to your doctor and your body.
zahid mahmood on January 07, 2014:
inr result is 1.8 tell me how many tablet ican us
Lena Welch (author) from USA on December 07, 2013:
Interesting. What brand are you using? I think the strips are different for each brand. I wonder if rubber gloves would help.
k stew on December 04, 2013:
I have a hard time with the strips I think they are hard to get out of the bottle they seem to stick together and then I end up grabing them in the wrong places and they err out.
Lena Welch (author) from USA on June 05, 2013:
I would ask your doctor about it. Like you said, getting blood draws all of the time is a pain. Your doctor can tell you if it is the right method for testing your INR.
Rebecca Rodriguez on June 05, 2013:
I have two mechanical heart valves n have to take warfarin for the rest of my life. Do u suggest I get a meter since now my inr is under control n checked less often? I would luv to have one! Beats goin to my cardiologist n getting vien draws..
Lena Welch (author) from USA on March 10, 2013:
I wish that I could answer that for you. I do not know what your insurance would cover. Each plan is different and workplaces sometimes have a say in what treatments you are allowed to have. Your best bet would be to do one of the following to get your answer:
1. You could call your insurance company and ask
2. You could have your doctor's insurance specialist call and ask
3. You could go to http://www.ptinr.com/home-inr-monitoring/it-covere... and read the guidelines that they have posted.
4. You could call PTINR.com (1.800.504.4394) and ask their benefits coordinator to help you get the answer (other home testing companies may do the same thing. I get nothing from this one, I just know that they offer that service).
I hope that one of those options helps you to find your answer.
Franco on March 10, 2013:
does blue cross pay anything?
Lena Welch (author) from USA on October 29, 2012:
I haven't seen a lot of talk about them here, but the support group for pulmonary embolism and dailystrength.com has people who use them.
I can tell you that my doctor used one for my testing. To summarize what I said in the hub... if you have APS and some other clotting conditions home testing and POC testing can be unreliable, not all doctors want to or are comfortable with home testing, not all insurance will pay for it (medicare and many are covering though for certain long term needs for certain diagnosis groups).
The anticoagulation clinic near me refuses to use them because they feel that they are unreliable. That being said, every single place I have researched has no issue for them as long as your diagnosis isn't contraindicated.
I understand that ptinr.com has helpful salespeople.
I would talk to your doctor and see if he or she uses one of these machines as a POC in the office. You could then get familiar with how they work and how the doc feels about them. Many docs are using them now as they offer instant reads on INR and then they can advise you on warfarin changes in person rather than having you on the phone or having you make two trips.
Jenny on October 27, 2012:
I am very interested in home testing as I have to test for life. I have very poor veins and sometimes takes 3 goes to find a good enough vein. I do not know anyone who has one to find the good or bad points. Can anyone help please
Jacob from Delhi, India on October 16, 2012:
Thanks for sharing it with us.
Lena Welch (author) from USA on July 29, 2012:
I have been thinking over your comment for some time now. I honestly have no clue. let me throw out some possibilities
1. The obvious - they like money
2. There are more people using glucose meters so the demand is higher and therefore the cost can be lower
3. There are still arguments about the reliability so many insurance companies (and doctors) don't want to use it
4. You still need a doctor's help with home INR. Home blood sugar you do not.
5. Glucose meters are MUCH older technology and therefore have come down in price over the years as they have become less expensive to produce
6. Glucose meters are often give aways because users use so many test strips. The test strips often only work in one type of meter. The companies are making the money off of the strips not the meters. (Similar to freebie ink jet printers)
I do know glucose meter users pay for strips. I worked for a guy who was diabetic but had no insurance. He was making bad choices by not testing his blood because he didn't want to spend the money on strips and not going anywhere to try to get free ones or free testing until he could pay.
sandi on July 28, 2012:
I would love to know...why are diabetics able to get low cost testing and those on coumadin are charged majorly for a similar equipment?
Lena Welch (author) from USA on May 03, 2012:
One of the anticoagulation clinics near me only did vein draws when I was on warfarin 3 years ago. They didn't feel that INR point of care machines were reliable. Every study told me that they were so I stuck with my family doctor who used one. If had a condition that interfered with the INR readings I would want a vein draw, but, I don't so POC made more sense to me.
I considered asking about home testing but decided just to wait it out as it was only a year of time. If I am ever on it for that long again though I would want home testing as work and travel interfere with going to a doctor's office. I don't know if my doc would be ok with it, but if he is, it seems like it would work better for me.
cave76 on April 14, 2012:
I test once a week and there is no maintenance other than a wipe down with an alcohol pad after using it...... and that's probably not necessary so often but I like to know that any medical device I use is always clean!
And entering the new test strip code each time I receive a different lot number (About 12 strips per box). But that's no problem at all.
If anything else goes wrong (with the machine itself) I'm sure the Alere people would take care of it pronto.
It seems that some people get a vein draw each time----- but I'm not clear as to whether that's because they have 'special' circumstances that dictate that or..........??? Perhaps a profit factor---- but that's just a supposition on my part.
Lena Welch (author) from USA on April 06, 2012:
Wow! That is great that insurance paid for it. I didn't home test when I had my clots but if I ever have have to go on warfarn for life or for another extended period I will be asking. I am trying to remember the INR machine my doctor used... no clue, but it worked and was much better than a vein draw!
How often do you test? Also, is there any maintenance you have to do for your INR machine?
cave76 on April 06, 2012:
I find home testing the easiest and best way to get my INR score.
No driving to the doctor's office. And esp. good for people who have a long drive to get to their doctor.
I use the Alere InRatio and the people at Alere are the best with answering any questions I had when first starting. I'm not saying others aren't as good--- Alere is the only one I have experience with.
My ins pays for it all----- but others with an insurance co. that isn't as great as mine is might not.