If you are being treated with the anticoagulant coumadin (Warfarin) for a heart condition like atrial fibrillation, you need to make frequent trips to a lab to be sure that your prothrombin time is in the right range.

The advent of new and accurate home-testing devices now makes it possible to test prothrombin time at home with a drop of blood, much like diabetes patient monitor their own blood glucose levels. Based on test results, you can either adjust the coumadin dose yourself or call your doctor for instructions.

A recent analysis of 14 randomized trials found that patients who measured and self-adjusted their coumadin doses had significantly fewer deaths and blood clots than those who did not. However, the self-testing group experienced no fewer major bleeding episodes.

Self-monitoring is not right for everyone. It's expensive and you need training and written instructions describing how to adjust your coumadin dose. You also need to be able to communicate quickly with your doctor to get the answer to any questions that may arise.

You might ask your doctor whether he or she thinks you are a candidate for self-monitoring. If the answer is yes, ask how you can get the necessary training and directions for how to modify your doses.