Should warfarin be discontinued or dose reduced before dental procedures involving anticipated bleeding?

There’s no set protocols for dental surgery. If warfarin is discontinued before surgery there will be decreased bleeding during the procedure and less bleeding post-op. The risks to pts include an increased risk of thrombus formation with catastrophic results (stroke, MI, pulmonary embolism, death… but their gums won’t bleed excessively!)


The New England Journal of Medicine recommends the following:

1. If INR 2.0-3.0, four scheduled doses of warfarin should be withheld to allow INR to fall spontaneously to 1.5 or less before surgery.
2. Warfarin should be withheld for longer period if baseline INR is normally held above 3.0
3. INR should be determined on day of surgery to assure adequate progress to the target (reduced) INR
4. Vitamin K (1.0mg s.c.) can be administered if required to bring INR to target level
5. “…patients who receive anticoagulants to prevent arterial embolism (mechanical valves, fibrillation…), the risk of embolism is not high enough to warrant either preoperative or postoperative therapy with intravenous heparin”
6. After surgery and warfarin is restarted, it takes about three days for the INR to reach 2.0 again. Thus, the pt has sub-therapeutic INR for approximately 2 days before and 2 days after surgery
7. Is there a risk of rebound hypercoagulability with this protocol?

The ADA says: “As the risk of localized bleeding after dental procedures (such as scaling, root planning and surgical procedures) can increase in patients taking anticoagulants, the dentist should consult with the patient’s physician to determine whether temporary reduction or withdrawal of the drug is advisable.”

You can do oral surgery without changing the pt’s warfarin dose by using anti fibrinolytic mouthrinse after the surgery. It is safer to leave the pt on his warfarin.

Category: Pharmacology Notes