Digitalis purpurea · PhytoNexus

01 Identity and provenance

Accepted binomial: Digitalis purpurea
Common names: Foxglove
Family (APG IV): Plantaginaceae
Part used: Leaf
Verification tier: Tier 2 · Verified Clinical columns reviewed and a source is on record.
Reviewer note (2026 audit): CORRECTED - Active chemical moiety: D. purpurea is the source of digitoxin; gitoxin/gitaloxin are the other principal glycosides. Ref: Drugs.com NPP monograph, Digitalis. | Synthetic drug analogue: Deslanoside is derived from lanatoside C of D. lanata, not D. purpurea; acetyldigitoxin is the closer semi-synthetic relative of digitoxin. | References link: Verified reference added.

02 Constituent chemistry

Chemical class	Marker compound	Synthetic analogue in use
Cardiac glycosides	Digitoxin (also gitoxin, gitaloxin) Leaf	Digoxin, Acetyldigitoxin

The analogue column is what makes the interaction reasoning tractable: where a constituent has a marketed structural counterpart, the counterpart's interaction profile is the starting hypothesis for the plant.

Looking up structures and physicochemical properties from PubChem…

03 Stated application

Reported activity: heart failure
Marketed in: Digoxin tablets
Reported adverse effects: digitalis toxicity

04 Interaction matrix

Source column, verbatim: Diuretics
Normalised onto 1 canonical drug class below.

Curated from the reviewed source

Drug class	Severity	Mechanism type	Provenance	Expected effect
Diuretics Renal	4Contraindicated	PD-additive + electrolyte-mediated	curated A	Hypokalaemia, hyponatraemia, dehydration, muscle weakness, cramps, arrhyt…	why ▾
Chemistry of this pair. Cardenolides and bufadienolides inhibit the sarcolemmal Na+/K+-ATPase directly, which is the same target as prescribed digitalis. Class mechanism. Aquaretic and saluretic botanicals add to renal potassium and sodium loss. Anthraquinone laxatives compound this through colonic potassium loss, and glycyrrhizin causes mineralocorticoid-like retention of sodium with kaliuresis. Expected Hypokalaemia, hyponatraemia, dehydration, muscle weakness, cramps, arrhythmia; potentiation of digoxin toxicity through low potassium. Management Check potassium, sodium and creatinine 1-2 weeks after starting. Avoid the combination entirely in patients also on digoxin. Onset rapid Evidence A - human data with a cited source Matched on “diuretics” Find evidence for this pair Map this mechanism

Predicted from constituent chemistry

These edges are not clinical findings. Each one is a rule inference: a constituent class in this plant is known to act on a target that the drug class also acts on. They are shown because a blank cell reads as “safe”, and for a Tier 1 entry a blank cell only means “not yet looked at”. Treat them as a literature-search agenda, not as a warning.

Drug class	Severity	Mechanism type	Provenance	Expected effect
Antiarrhythmics Cardiovascular	4Contraindicated	PD-additive + electrolyte-mediated	predicted D	Proarrhythmia, QT prolongation, torsade de pointes, ventricular arrhythmi…	why ▾
Chemistry of this pair. Cardenolides and bufadienolides inhibit the sarcolemmal Na+/K+-ATPase directly, which is the same target as prescribed digitalis. Class mechanism. Botanicals that shift potassium or magnesium, block sodium or potassium channels, or prolong repolarisation add to class I and class III antiarrhythmic effects on an already unstable myocardium. Expected Proarrhythmia, QT prolongation, torsade de pointes, ventricular arrhythmia. Management Avoid. If unavoidable, baseline and follow-up ECG with QTc measurement plus potassium and magnesium correction. Onset rapid Evidence D - in silico rule prediction only Find evidence for this pair Map this mechanism
Cardiac glycosides (digoxin, digitoxin) Cardiovascular	4Contraindicated	PD-additive + PK-transporter + assay interference	predicted D	Nausea, xanthopsia, bradyarrhythmia, AV block, ventricular tachycardia an…	why ▾
Chemistry of this pair. Cardenolides and bufadienolides inhibit the sarcolemmal Na+/K+-ATPase directly, which is the same target as prescribed digitalis. Class mechanism. Cardenolide- and bufadienolide-bearing plants are themselves Na+/K+-ATPase inhibitors, so co-administration is pharmacological overdose. Several also inhibit intestinal P-glycoprotein, raising digoxin exposure, and cross-react with digoxin immunoassays so that serum levels become uninterpretable. Expected Nausea, xanthopsia, bradyarrhythmia, AV block, ventricular tachycardia and death; falsely reassuring or falsely high assay results. Management Treat as an absolute contraindication. If exposure has occurred, manage on ECG and clinical grounds, not on assay values, and consult toxicology about digoxin-specific Fab. Onset rapid Evidence D - in silico rule prediction only Find evidence for this pair Map this mechanism

05 Hazard register

The audit recorded no hazard beyond the interaction profile. The controlled-vocabulary field reads not assessed, which means the assessment has not been done rather than that it came back clear.

06 Confusable material

These entries could be mistaken for this one in trade, in the herbarium, or in a prescription. Powdered material is often indistinguishable, so the check is macroscopic, microscopic and chromatographic rather than nominal.

Digitalis lanata

Woolly Foxglove (Grecian Foxglove)

Plantaginaceae

Same genus (Digitalis)

07 Mechanism map

Chemistry sorts to the left, pharmacology to the right. Dashed edges are predicted. Drag nodes, scroll to zoom, export at 3× for a figure.

species

chemical class

marker compound

drug class

expected effect

hazard

08 Open literature

Abstract-scoped query built from this binomial, its common names and its marker compounds, run live against Europe PMC, PubMed and OpenAlex, then ranked locally against an evidence hierarchy.

Checking openFDA spontaneous reports…

09 Isomechanistic neighbours

Species whose interaction profile overlaps this one, ranked by shared severity weight rather than by count — a shared contraindication counts for more than a shared minor signal. Practical use: these are the plants you should not stack with this one, because the mechanisms summate.

Species	Family	Shared classes	Jaccard
Digitalis lanata Woolly Foxglove (Grecian Foxglove)	Plantaginaceae	3	1.00
Nerium oleander Kaner (Oleander)	Apocynaceae	3	1.00
Cascabela thevetia Yellow Oleander	Apocynaceae	3	1.00
Urginea indica Indian Squill	Asparagaceae	3	1.00
Drimia maritima European Squill	Asparagaceae	3	1.00
Convallaria majalis Lily of the Valley	Asparagaceae	3	1.00

10 References and notes

Source column: https://www.drugs.com/npp/digitalis.html

https://www.drugs.com/npp/digitalis.html

manual

BibTeX for all 1 records

@article{anon,
  url = {https://www.drugs.com/npp/digitalis.html},
}

Curator notes

No notes yet.

Sign in to add notes and save monographs.