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.
Vasodilator, diuretic, ACE-inhibitory and calcium-antagonist activity in botanical extracts adds to prescribed blood-pressure lowering. A minority (ephedrine-, glycyrrhizin- and caffeine-bearing) act in the opposite direction and antagonise control.
Expected clinically: Orthostatic hypotension, dizziness, syncope and falls; or loss of blood-pressure control with pressor botanicals.