HEALTHLINE (Medstar) -- In the future, blood-thinner patients may have a special test before they take their first pill.
Doctors consider many factors before blood-thinning medication is prescribed, but some clues are hidden. As janet vasil reports, it may become more common to have a gene test before you get your coumadin.
After surgery to replace a heart valve, Robert McNeilly started taking the blood-thinner warfarin.
"When they said, ‘You know, this is rat poison, don't you?' I said, ‘Well are you sure it's safe for me to take?'"said Robert McNeilly Jr.
All joking aside, the medicine requires regular follow-up.
"If it kind of gets off, then usually they'll say, ‘Well let's try two weeks. Come in ‘til we can stabilize it,'" said McNeilly Jr.
Like Robert, many use blood-thinners without a problem. But, genetic variants can change the way the drug is metabolized.
Iif you have one variant, you might be down to 4-½ milligrams a day. If you have a more serious variant, you might be down to 4 milligrams a day. But if you have two serious variants, you might be down to 1 milligram a day," said Dan Roden, M.D.
This sort of genetic quirk can be dangerous.
"Now this is a drug that it makes a big difference if your target dose is 1 milligram and you take 5 milligrams - you've way overdosed yourself," said Dr. Roden.
Tests are now approved to detect warfarin-sensitivity, but they aren't widely available.
"It is very difficult, right now, for a physician to write an order to get a genetic test that is delivered in a timely fashion," said Dr. Roden.
For the time-being, Doctor Roden says standard practice will continue.
"I think it's still in the research realm. But, but, there's great hope that this will be part of a, of a real change in the way we deliver care," said Dr. Roden.
Taking us all forward into the world of genetically-personalized medicine. This is janet vasil reporting.