Clint Eastwood as Terry McCaleb may have needed blood thinners after a heart transplant in “Blood Work,” but that couldn’t keep the movie’s plot moving along smoothly. In the real world, the blood thinner Coumadin (generic name warfarin) is used to protect 2 million people in North America every day from the risk of stroke -- especially those with abnormal heartbeats (atrial fibrillation). But it’s a tough drug to take and tougher still to make sure it does more good than harm: Blood tests, sometimes more than once a week, are needed to make sure you aren’t in danger of either internal bleeding or a blood clot.

We YOU Docs are delighted to tell you that things are changing. An international research group is putting together a formula (computer program) based on genetic testing, body mass index, age and gender, that will tailor-make a warfarin schedule just for you. (You’ll still have dietary restrictions; no wheat germ, Brussels sprouts, spinach or green tea, for example.)

And newer drugs are replacing warfarin: They don’t require regular blood tests to check dosing and have no dietary restrictions. The Food and Drug Administration has approved three. Their drawback -- unlike warfarin -- a lack of antidote, so they may cause prolonged bleeding if you cut yourself, for example.

If you’re prescribed blood thinners, make sure you follow instructions carefully, pay attention to blood test results, and talk to your doc about what is best for you. When taken properly, they are real lifesavers.

The YOU Docs, Mehmet Oz, host of “The Dr. Oz Show” and Mike Roizen of Cleveland Clinic, are authors of “YOU: Losing Weight.” For more information go to www.RealAge.com.