Not Only Atrial Arrhythmias: A Historic Ethnopharmacological Analysis of Foxglove (Digitalis purpurea L.)

Background: Cardiac glycoside-containing plants have played an important role in the history of cardiovascular medicine. Among these, foxglove (Digitalis spp.) became particularly significant following William Withering’s systematic observations of its therapeutic use, published in 1785. Although foxglove preparations were primarily associated with the treatment of dropsy and cardiac disorders, nineteenth-century physicians also explored their use in a wide range of other conditions. This review aims to describe the use of Digitalis-based preparations in professional medical practice between 1785 and 1900, with particular attention to their pharmaceutical forms, dosage regimens, therapeutic indications, and reported effects. Methods: Literature searches were conducted in JSTOR, PubMed, and Google Scholar using the keywords “Digitalis”, “Foxglove”, and “Fox-glove”. Historical publications identified through reference lists were also considered. Sources were selected for their relevance to Digitalis preparations, dosage forms, and therapeutic applications. Primary historical sources formed the basis of the analysis, while later historical and modern publications were used for contextual interpretation. Results: The reviewed sources document the use of Digitalis preparations for dropsy and cardiovascular disorders, as well as for conditions including pneumonia, delirium tremens, epilepsy, haemorrhage, and febrile illnesses. Preparations included powdered leaves, infusions, decoctions, tinctures, and extracts, with substantial variation in dosage and administration. The sources also document concerns about adverse effects and the dangers associated with excessive dosing. Conclusions: Nineteenth-century medical practice employed Digitalis in a broader range of conditions than those associated with its contemporary clinical use. The contemporary clinical use of Digitalis glycosides is mainly limited to selected patients with atrial fibrillation for ventricular rate control and selected patients with symptomatic heart failure with reduced ejection fraction, owing to their narrow therapeutic index.