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Foxgloves: Toxic Landscape Perennial Often Mistaken for Comfrey

With their ornamental spires of bell-shaped flowers, foxgloves, or Digitalis, are an attractive group of herbaceous perennials. They’re popular in gardens, but many are unaware of their lethal potential. The name ‘foxglove’ has a charming allure, but digitalis is known by a number of other ominous names including, ‘witch’s gloves’ and ‘dead man’s bells’.

Ingesting foxglove won’t just make you ill — it has a life-threatening effect on heart rate and it can be fatal. Although there are a number of differences, novice foragers and well-meaning but inexperienced herbalists may mistake foxglove for the edible comfrey.

A large group of over 10 foxgloves and their bright pink spires of flowers.
Digitalis purpurea on the edge of a forest | Photo by Kazaar on Wikimedia Commons

What Are The Active Compounds in Foxglove?

Foxglove contains toxins known as cardiac glycosides. They can have an incredibly serious effect on the minerals within heart cells and can slow, block or increase the heart rate. The entire plant contains these toxins, from the seeds right down to the roots. And it’s not only toxic to humans, with all pets and livestock susceptible to its toxicity too.

The medicinal name for these compounds is digoxin. There is an antidote to foxglove poisoning known as digoxin-Fab, which can aid in patient recovery.

5 vials of digoxin medicine in a plastic container, placed on a bright yellow table.
Digoxin vials | Photo by Wesalius on Wikimedia Commons

Foxglove Poisoning Symptoms

Symptoms begin roughly two hours after ingestion, and will generally involve severe nausea, a slow pulse, fatigue, chest pains, and a very irregular heart rate.

Treatment is possible, but permanent damage to the liver or heart may be caused. There was a recent case in January 2021 in Ireland where a man ingested a cocktail that contained two single leaves. He was in the hospital for 10 days.

Cultural Symbolism of Foxglove

Foxglove often features in films and tv as a poison, with possibly the most famous appearance in a James Bond film. In the film, Casino Royale, Bond’s cocktail is poisoned with digitalis by the lead villain, and Bond goes into cardiac arrest.

The effects that foxglove can have on heart rate were formally identified in 1785 by William Withering. As a botanist, he became interested in a herbal cure for dropsy created by a herbalist known as ‘Mother Hutton’. Today, dropsy is medically known as edema and can be caused by conditions like congestive heart failure.

A black and white image, with Mother Hutton holding a cane, sat on a wall, and handing William a folded piece of paper.
A painting of William Withering and Mother Hutton | Image from William Meade Prince, on Wikimedia Commons

What is the Medicinal Potential of Foxglove?

Since the medicinal potential was formally identified, the digoxin in foxglove has been extracted and used in a number of heart medications. It is not recommended for self-medication or homemade remedies due to its incredibly strong effect on the heart. It can treat atrial fibrillation and also heart failure.

A black glass bottle with an old paper cap and label reading... "Burroughs Wellcome & Co. Digitalis Tincture. Each represente, min. 5 (0.296 c.c.). Direction. — One may be taken twice or thrice daily, with a little water, after food. To be taken with great Caution. Snow Hill Buildings, LONDON, E.C."
Bottle of ‘Digitalis Tincture’ from the medicine chest supplied by Burroughs Wellcome & Co., which accompanied the 1901 National Antarctic Expedition | Photo from Wikimedia Commons

What Do Foxglove’s Look Like?

There are 27 recorded foxglove species in the digitalis genus and a wide number of varieties that have been hybridized by avid gardeners. Most species have tall spires of tubular flowers in warm pinks and purples — although other species may have orange, yellow, or white petal colors. The wide pointed leaves grow out radially from a central stem.

The bell shaped flower showing the speckled inside.
Close up of a pink foxglove flower | Photo by AnemoneProjectors on Wikimedia Commons

The most common and recognizable species is the Digitalis purpurea which is native to Europe. It is widely naturalized in other continents, particularly the US, because of its value as an ornamental plant. The pink flowers usually have an internal spotted pattern.

Where Do Foxglove’s Grow?

Foxgloves are native to most temperate areas in Europe, Asia, and Africa. It favors a wide range of habitats, from open meadows and deeply shaded woodland, to coastal cliffs and humid laurel forests.

A single digitalis plant on bare soil surrounded by other emerging Spring plants.
Digitalis Leaves in a woodland | Photo by Agnes Monkelbaan on Wikimedia Commons

Conclusion

The hugely toxic nature of foxglove has no effect on its desirability as a garden ornamental. It’s loved in cottage gardens in the UK and is a striking wild plant that can always be admired throughout the summer months on a hike or walk. Just be wary of children and pets encountering them, as they can be extremely deadly if accidentally consumed.

Featured Image: Digitalis Purpurea in the Netherlands | Photo by Matthijs van den Berg on Wikimedia Commons

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