ISSN : 0376-4672
The vitamin K antagonist (VKA), cumadin, or warfarin, is the only antithrombotic drug that can be orally administered and has excellent effective for decades. However, it is cumbersome to periodically inspect the prothrombin time (PT) order to maintain adequate concentrations that do not cause bleeding, takes a few days to indicate therapeutic effects, gets affected by several factors such as food and drugs etc, and narrow in the therapeutic range. Although recently in development, the non-vitamin K antagonist anticoagulants(NOACs) exhibit a rapid onset of action and have relatively short half- lives compared to Coumadin. Because of these pharmacokinetic properties, it is possible to modify an individual's anticoagulation status quite rapidly, minimizing the period where the anticoagulation activity is therapeutically sub-optimal. And the short half -lives of these drug allow for the relatively rapid reduction of their anticoagulation effects. There are currently no published clinical trials specifically assessing the bleeding risks associated with dental procedures for patients taking the NOACs. It is not necessary to interrupt NOAC medication for dental procedures that are likely to cause bleeding, but which have a low risk of bleeding complications. Because the bleeding risk for these procedures is considered to be low, the balance of effects is in favour of continuing the NOAC treatment without modification, to avoid increasing the risk of a thromboembolic event. The patients should be advised to miss(apixaban or dabigatran) or delay(rivaroxaban) a dose of their NOAC prior to dental procedures that are likely to cause bleeding and which have a higher risk of bleeding complications. Because the risk of bleeding complications for these procedures is considered to be higher, the balance effects is in favour of missing or delaying the pre-treatment NOAC dose. The interruption is only for a short time to minimize the effect on thromboembolic risk,
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