Six public APIs, no keys and no paywall. Queries are scoped to title and abstract rather than full text, because a full-text hit on Curcuma in a reference list is not evidence of anything. Everything retrieved is then passed through an interaction-vocabulary gate: a paper is admitted only if it actually describes an interaction, not merely because it names a plant and a drug in the same abstract. What survives is ranked against an eight-level evidence hierarchy, so a randomised trial outranks a review that cites it.
Coumarin-, salicylate- and coumestan-bearing botanicals add to vitamin-K-antagonist effect; several also compete for CYP2C9 and CYP3A4, raising S-warfarin exposure. Botanicals rich in vitamin K1 act in the opposite direction and blunt anticoagulation.
Expected clinically: INR destabilisation in either direction; ecchymosis, epistaxis, gum bleeding, GI or intracranial haemorrhage.