The foxglove plant is the perfect example of how the same plant can cure or kill. In the seventeenth century, in England, foxglove was given for the first time to an ill person who suffered from a heart-caused case of dropsy (edema in the whole body caused by heart failure). A few years later, the foxglove plant was included in the Edinburgh Pharmacopoeia.
From then on, much biochemical and biological research on this plant has been carried out, whose active components have not yet been substituted by any chemical product.
Presently, the foxglove plant glycosides are widely employed in medicine and have saved many lives of people with heart-related issues. However, the foxglove plant is very toxic. An infusion with a minimum part of only one leaf (10 g) may cause an adult person’s death.
It is a problem of dosage. The therapeutic range is very narrow, and the poisonous dose is very close to the medicinal one. There are significant variations in the concentration of active components depending on the place where the plants grow, the gathering season, the drying time the plant takes, etc.
Pharmacological industries have isolated those active principles, making them chemically pure. Thus, it is easier to dose and apply them correctly. However, their effectiveness is lower because other substances usually present in the plant, which complement, do not appear together with chemically pure active components.
Foxglove Plant Preparation and Use
- Pharmaceutical preparations. The safest and most tolerated method to apply foxglove is to use its extract in pharmaceutical preparations. However, the complete plant’s use is more beneficial, though more caution is required to administer the correct dose. Only pharmacists and physicians with experience in phytotherapy can obtain the maximum advantage of this powerful plant. If correctly applied, it can solve severe heart problems and even save lives.
- Infusion. With one gram of powder obtained from dry ground leaves per 100 ml of hot water. Steep for 15 minutes. Drink during the day, by spoonfuls. Do not exceed this dose. It must never be taken continuously for more than ten days because the glycosides accumulate in the body. Usually, it is taken for five days, with a two-day pause.
- Compresses. Preparing an infusion with one or two leaves per liter of water, then soaking cotton cloths applied to the affected skin area.
- Excellent wound healing agent: In external use, the leaves of the foxglove plant are a perfect wound healing agent for ulcers and skin wounds, including varicose ulcers. This was the main application of foxglove until its effects on the heart were discovered.
- Synonym: Digitalis, dead men’s bells, dog’s fingers, fairy fingers, fairy gloves, finger flower, folks’ glove, lion’s mouth, ladies’, glove, purple foxglove, American foxglove.
- French: Gant de Notre Dame, digitale.
- Spanish: Digital, dedalera.
- Habitat: Common in siliceous lands in the mountainous areas of Western Europe.
- Description: Biennial plant of the Scrofulariaceae family, growing up to one and a half meters high. Large, velvet-like, lanceolate leaves which grow from the lower part of the plant. Its flowers are finger-shaped, purple or pink colored, and grow from the of the stem.
- Parts used: Leaves.
Foxglove Plant Properties and Indications
Two kinds of substances may be distinguished in foxglove:
- Non-glycosides: Digitoflavine (yellow coloring), cyclohexanol, malic and succinic acids, tannin, and an oxidizing diastase. These substances do not have a direct effect on the heart, though they complement and improve glycosides’ action.
- Glycosides: They are responsible for the cardiotonic effects of the foxglove plant on the heart muscle. The most important ones are digoxin and digitalin. They have the following properties: Increases strength of the heart contractions, improving its mechanical performance, Balance the heartbeat rate when it is irregular or too quick.
WARNING: Though foxglove is a toxic plant, accidental intoxication is rare due to its disagreeable flavor. Chewing its leaves or flowers irritates the mouth and causes nausea, vomiting, vision alterations, bradycardia, and ultimately heart failure. A few flowers may cause death in a child.
First aid consists of a stomach pumping, administering purgatives, activated charcoal, and urgent transportation of the afflicted person to a hospital.
George D. Pamplona-Roger, M.D. “Encyclopedia of Medicinal Plants.” George D. Pamplona-Roger, M.D. Encyclopedia of Medicinal Plants. Ed. Francesc X. Gelabert. vols. 1 San Fernando de Henares: Editorial Safeliz, 2000. 221,222. Print.