I am 74 years old and taking coumadin. I take 2.5 mg three days a week and 5 mg the other four days. Can I have a colonoscopy? Is there a way to get around the potential bleeding problem?

N.

The issue of anti-clotting (anticoagulant) medications, such as coumadin, and colonoscopy has received much attention. Although the colonoscopy exam per se does not pose a significant risk of bleeding, certain procedures that may need to be done during colonoscopy may pose a risk for bleeding.

Some procedures, such as biopsy, are relatively unlikely to cause bleeding and thus can be done in a patient who is on anticoagulant therapy. Other procedures, such as polyp removal, are more invasive and involve more tissue damage. These place the patient at higher risk of bleeding and are most safely done when the patient is off anticoagulants.

The risk of bleeding in patients taking anticoagulants must also be weighed against the risk of complications from stopping the anticoagulants before the colonoscopy. Patients take anticoagulants for various reasons, including prevention of strokes, prevention of pulmonary emboli (blood clots that travel to the lungs), prevention of clots on metallic heart valves and, in some instances, for regulation of abnormal heart rhythms. Some of these disorders require intensive levels of anticoagulants and close monitoring of the patient's blood. In such cases, stopping the anticoagulant even for a short period of time may place the patient at high risk for clotting complications.

Thus, the decision about whether or not to stop coumadin or other anticoagulants before a colonoscopy should be made by the patient's primary care doctor (or cardiologist) in consultation with the gastroenterologist performing the procedure. In some cases, it is safe to withhold the anticoagulants for several days before the procedure. In other more risky cases, the patient stops oral anticoagulants and is brought into the hospital several days before the procedure for intravenous anticoagulation therapy, which can be halted a few hours before the colonoscopy to minimize the time that the patient is off the anti-clotting drugs.

Generally, it is preferable to perform colonoscopy when the patient is off anticoagulants (except in emergency cases when it may not be an option) so that any necessary procedures can be done during the exam. In your case, you should have your primary doctor discuss your coumadin regimen with the gastroenterologist so a decision can be made about how to proceed.