This article examines the medical and political discussions regarding a controversial medicinal bark from Ecuador – cundurango – that was actively sponsored by the Ecuadorian government as a new botanical cure for cancer in the late nineteenth century United States and elsewhere. The article focuses on the commercial and diplomatic interests behind the public discussion and advertising techniques of this drug. It argues that diverse elements – including the struggle for positioning scientific societies and the disapproval of the capacities of Ecuadorian doctors, US abolitionist history, regional and local political struggles – played a role in the quackery accusations against cundurango and its promoters. The development and international trade of this remedy offer interesting insights into the global history of drugs, particularly how medical knowledge was challenged during a period when scientific medicine was struggling for hegemony. It explores how newspapers expanded “the public interest” in a possible cancer cure.