What severe risk increases when ginger is combined with prescription drugs like Warfarin (Coumadin)?

Amplified anti-platelet effect leading to increased bleeding risk.

The most serious contraindication for high-dose or routine ginger supplementation involves its natural anti-platelet activity, which is the ability to inhibit blood clotting. Warfarin, marketed under the name Coumadin, is a powerful anticoagulant (blood thinner) prescribed to prevent dangerous clots. When ginger is introduced alongside Warfarin, its own platelet-inhibiting properties are added to the medication's effect. This synergistic interaction significantly amplifies the blood-thinning capacity, moving the patient from a therapeutic level of anticoagulation into a potentially hazardous zone. This heightened effect increases the probability of unintended side effects such as easy bruising, persistent nosebleeds, or, critically, severe internal hemorrhaging, necessitating extreme vigilance from the patient.