Foxgloves: Beautiful Flowers and Digitalis Health Effects

A pink foxglove in bloom
A pink foxglove in bloom | Source

Dangerous and Useful Flowers

Foxgloves are beautiful flowers that grow in both a wild and a cultivated form. They are admired for their tall spires containing multiple rows of large, tubular flowers. Foxgloves are notable for more than their beauty, however. They contain a chemical called digitalis. Although this chemical can be dangerous, in small quantities it's used to make a heart medicine.

Digitalis increases the force of the heartbeat. This effect is helpful in a disorder known as congestive heart failure. It also helps to treat a type of irregular heartbeat known as atrial fibrillation. There is a world of difference between taking a prescribed dose of digitalis medicine and ingesting the digitalis in a foxglove plant, however. The plant is poisonous.

The scientific name of the common foxglove is Digitalis purpurea. The species has purple, pink, yellow or white flowers. It's native to Europe but has been introduced to North America. The plant is very attractive and is admired by many people, despite its dangers.

A group of foxgloves can be an attractive sight.
A group of foxgloves can be an attractive sight. | Source

How Did the Foxglove Get Its Name?

It's uncertain how the name of the foxglove plant was derived, but there are two main theories.

  • A commonly accepted idea is that the name came from the Anglo-Saxon term "foxes glofa", which means "glove of the fox". The flowers do fit over a human finger nicely, like the fingers of a glove or like a thimble, but why the reference to foxes? Perhaps because of the legend which said that fairies gave the flowers to foxes so that they could put them on their toes and then silently approach and kill a family's chickens.
  • Some investigators have suggested that the plant name has nothing to do with foxes. Instead, they believe that the word "fox" developed from the word "folk's". Folk was another name for fairies.

Foxgloves may or may not have been named after foxes. This is a European red fox.
Foxgloves may or may not have been named after foxes. This is a European red fox. | Source

Foxglove Plants

Foxgloves are often hard to ignore when they are in bloom, especially when they're growing in a group. The spires may be as tall as six feet. The flowers are often pink but may also be purple, lavender, yellow, peach, orange, rusty brown or white. Some plants produce spires which have flowers of more than one colour. The opening of the flowers is often decorated with blotches of various colours.

Foxgloves are thought to be native to Europe, Asia and Northern Africa. They have been introduced to many other parts of the world, however. There are about twenty species, most of which are biennial. In the first year of its life, a foxglove plant consists of a low rosette of leaves. It doesn't flower until the second year. The leaves are oval in shape and have pointed tips. They are attached to the flower stem in an alternate arrangement.

Inside a foxglove flower
Inside a foxglove flower | Source

Bees are attracted to the nectar in foxgloves and are common pollinators of the flowers.

A Bumble Bee Pollinating Foxgloves

A Poisonous Plant

The flowers, seeds, leaves, stem and sap of foxgloves are all poisonous. Human poisoning isn't common, however. The leaves don't taste very good, so most people quickly spit the plant out if they sample it. However, some people have mistaken foxglove leaves for comfrey leaves and have been poisoned when they've made an infusion or tea from the leaves. (Comfrey is a controversial plant and is considered to be unsafe by some investigators.)

Children may be attracted to the interesting, bell-shaped flowers of foxgloves. They mustn't be allowed to suck liquid from the bells, however, as sometimes happens, nor drink water from a vase in which foxgloves have been standing.

The toxicity of a particular foxglove plant depends on several factors, including how much toxin is present in the part that is eaten and the individual susceptibility of the person who eats the plant. The symptoms resulting from foxglove ingestion range from mild gastrointestinal problems to serious nervous system and heart effects that require emergency medical treatment.

In the past, people drank herbal infusions made from foxglove leaves and also used the leaves as a compress for wounds. The ingestion of foxglove was risky, but it did show that the plant could be helpful in some situations.

Foxgloves outside an English church. The spire in the foreground bears flowers of two different colours - pale yellow and light pink.
Foxgloves outside an English church. The spire in the foreground bears flowers of two different colours - pale yellow and light pink. | Source

William Withering and the Discovery of Digitalis

William Withering was a doctor and botanist who lived in the eighteenth century. He investigated the effects of foxglove on dropsy. "Dropsy" was the old name for a condition that we call edema today. Edema refers to the collection of fluid in body tissues. Congestive heart failure is often accompanied by edema.

Withering decided to do his research after seeing the success of a herbalist at treating dropsy. The woman give her patients a mixture of many different herbs. Withering patiently tested each component of the mixture and found that foxglove was responsible for the beneficial effects.

Withering found that an infusion of foxgloves leaves could slow and strengthen the heartbeat. He also found that a high dose of foxglove leaves could stop the heartbeat instead of helping it. He named the active ingredient in foxglove "digitalis" after the first word in the plant's scientific name.

How to Grow Foxgloves in a Garden

Digitalis, Digoxin and Digitoxin - What's the Difference?

The terminology concerning digitalis is sometimes confusing.

  • When the chemical is inside a foxglove it's known as digitalis.
  • When digitalis from Digitalis lanata leaves is prepared as a medication it's known as either digitalis or digoxin. Digoxin is the generic name of the medicine. A common brand name is Lanoxin.
  • When digitalis from Digitalis purpurea is prepared as a medication it's known as either digitalis or digitoxin. Digitoxin has also been obtained from some other foxglove species.

Digoxin and digitoxin have almost identical chemical structures. Digoxin has one hydroxyl group (OH) that digitoxin lacks, however. In North America, digoxin is generally prescribed instead of digitoxin.

Digitalis lanata - the Grecian or Woolly Foxglove
Digitalis lanata - the Grecian or Woolly Foxglove | Source

Health Benefits of Digitalis

Digitalis is a type of medication known as a cardiac glycoside. Cardiac glycosides are used to treat heart failure and an irregular heart beat (cardiac arrhythmia).

The term "heart failure" doesn't mean that the heart has stopped beating, but it does mean that the heart can no longer pump enough blood to satisfy all the body's needs. The disorder is also known as congestive heart failure or CHF. It develops after the heart has been damaged or weakened. As a result of the decreased effectiveness of the heartbeat, blood collects in blood vessels and fluid from the blood escapes into tissues, causing congestion.

Digitalis helps heart failure because it causes the heart to beat more strongly. Digitalis also slows the heartbeat, which is useful in the treatment of certain heart disorders.

Three foxgloves
Three foxgloves | Source

How Does Digitalis Strengthen the Heartbeat?

Digitalis increases the force of the heartbeat. It does this by stimulating the buildup of calcium in heart muscle. Calcium is a vital element in the body because it enables muscles to contract.

The heart is made of muscle cells. Like other cells, heart cells are covered with a membrane, which contains proteins called receptors. Chemicals from the outer and inner environments of the cell join to the receptors, triggering certain effects as they do so.

Digitalis interferes with the action of two membrane proteins, thereby allowing calcium to build up. It does this in the following way.

  • A membrane protein called the sodium-potassium pump moves potassium into the heart cells and sodium out of the cells. This activity is a normal part of a cell's life.
  • Digitalis binds to the pump and stops it from doing its job, allowing sodium to build up in the heart cells.
  • The high level of sodium in a heart cell alters the activity of another membrane protein called NCX, which stands for sodium-calcium exchanger. (The "N" comes from Na, which is the chemical symbol for sodium.)
  • NCX moves sodium in one direction through the cell membrane and calcium in the other direction.
  • Each chemical can be carried either into the cell or out of the cell by NCX. The predominant direction of chemical flow depends on environmental conditions.
  • The high level of sodium inside the cell when digitalis is present causes NCX to increase its movement of sodium out of the cell and calcium into the cell
  • These changes serve to increase the amount of calcium in the heart cells, enabling the heart to contract more strongly.

As shown in the video below, sodium (Na), potassium (K) and calcium (Ca) actually exist as ions in the body. An ion is an atom that has lost or gained electrons and developed a charge.

Actions of Digoxin in the Body

An Irregular Heartbeat or Atrial Fibrillation

The term "arrhythmia" refers to the altered rate or rhythm of the heartbeat. The heart may beat too fast, too slow, or irregularly. A common type of arrhythmia - the type that digitalis helps - is called atrial fibrillation.

The atria are the two upper chambers of the heart, which contract before the two lower chambers, or ventricles. During atrial fibrillation, the atria quiver or flutter rapidly instead of contracting. This process interferes with blood flow through the heart.

A Diagram of the Human Heart

Source

In the human body, the terms "right" and "left" are applied from the owner's point of view and not the viewer's.

The Origin of the Heartbeat

The sinoatrial node, or SA node, is a patch of tissue in the upper part of the right atrium that triggers the heart beat. The node is sometimes known as the pacemaker of the heart.

In a normal heartbeat, the SA node sends an electrical impulse through the atria, causing them to contract. The impulse reaches the atrioventricular node, or AV node, which is located at the bottom of the right atrium. The AV node then causes the contraction of the ventricles. When the ventricles contract, blood is sent out of the heart to the body.

The heart rate established by the SA node can be modified by the nervous system. Sympathetic nerves speed up the heart rate and parasympathetic nerves slow it down.

Conduction System in the Heart

1 = sinoatrial or SA node; 2 = atrioventricular or AV node
1 = sinoatrial or SA node; 2 = atrioventricular or AV node | Source

Digitalis and Heart Rate in Atrial Fibrillation

Digitalis slows the activity of the AV node, thereby slowing the contraction of the ventricles. It also increases the parasympathic nerve stimulation of the SA node, which slows the contraction of the heart as a whole.

Although digitalis is often prescribed to increase the strength of the heartbeat, some doctors today prefer to use other medications instead of or in addition to digitalis to treat atrial fibrillation.

Rusty Foxglove Flower Opening Time Lapse

Digitalis Toxicity

Diigitalis can be an extremely useful medicine for heart problems, but it can also be very toxic. It can save lives or end them, depending on its dose. The difference between an effective digitalis dose and a harmful one is quite small. Therefore anyone taking digitalis needs to be monitored by a doctor.

A patient doesn't need to be afraid of taking digitalis if their doctor prescribes it. The medication could be a wonderful help for the person's heart problems. However, because of the possibility of side effects and of interactions with other medications, it's essential that digitalis is taken with a doctor's guidance.

One example of a possible digitalis complication is related to the use of diuretics and the amount of potassium in the body. Since digitalis interferes with the action of the sodium-potassium pump, it reduces the amount of potassium that enters cells. People with congestive heart failure often take a diuretic medication, which increases fluid loss from the body in urine. Potassium may be excreted in the urine, further reducing the level of potassium in the body. A doctor may prescribe a potassium supplement or a potassium-sparing diuretic in this situation. Potassium-sparing diuretics increase water loss in urine but not potassium loss.

Different colours of foxglove flowers on the same stem
Different colours of foxglove flowers on the same stem | Source

Possible Symptoms of Digitalis Toxicity

The following symptoms could be due to digitalis toxicity, although they could arise due to other causes as well. Anyone taking digitalis should pay close attention to these symptoms.

  • stomach upset
  • nausea and vomiting
  • diarrhea
  • headache
  • loss of appetite

More serious changes may include:

  • vision changes (such as blurred vision, blind spots and changes in colour perception)
  • irregular breathing
  • heart palpitations
  • irregular heartbeat

For many people digitalis toxicity will never be a problem. If foxgloves are admired but not eaten and if medication instructions are followed carefully, the plant can be appreciated for both its beauty and its health benefits. It's important that anyone involved with foxgloves or digitalis remains vigilant and watches for harmful effects, however.

Foxgloves in Sweden
Foxgloves in Sweden | Source

© 2013 Linda Crampton

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Comments 42 comments

Suzie HQ profile image

Suzie HQ 3 years ago from Dublin, Ireland

Hi Alicia,

How interesting this hub is! I love foxgloves and found the folklore theory lovely. The idea of fairies putting the flowers on foxes toes is so mystical and suits this stunning flower. The connection with digitalis is fascinating and great to know for all of us. Fabulous photos as always and well done on all the research it really shows - you have delivered another epic!

Voted up ++++, shared and pinned!


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you so much for the lovely comment, Suzie! I appreciate the vote, the share and the pin, too! Foxgloves are beautiful and interesting flowers. I'm always happy to see them.


billybuc profile image

billybuc 3 years ago from Olympia, WA

I have never grown these but perhaps next year I'll give them a try. They look great in a perennial garden, don't they?

Thanks for the info, Alicia, and I hope you have a great Monday.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Bill. Thanks for the visit. Foxgloves do look attractive in gardens! I hope you have a great Monday as well.


Pamela99 profile image

Pamela99 3 years ago from United States

This is an excellent article on Foxglove. It is such a beautiful flower, but doesn't grow in FL. I gave digitalis to many patients when I was a nurse. as it is a very effective and I believe the oldes known heart medication. I wonder how many other flowers and plants hold the cure for diseases. Your article is so well done with a great explanation of the effectiveness of Foxglove and all the beautiful pictures. Awesome hub!


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you very much for the comment, Pamela99! I appreciate your visit. It's interesting to hear about your experience with digitalis. There may be many useful medicines in plants, which is one reason why it's important that a wide range of plants continues to exist on Earth. It would be sad if a plant containing an important medicine became extinct!


kashmir56 profile image

kashmir56 3 years ago from Massachusetts

Hi my friend great informative article on this very beautiful flower, most of it i did not know before, thanks for help me learn about this interesting information on foxgloves .

Vote up and more !!!


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thanks for the comment and the votes, Tom! I appreciate your visit, as always.


drbj profile image

drbj 3 years ago from south Florida

Hi, Pamela. What a fascinating article on foxgloves, digitalis and and how this beautiful flower may have received its name. Enjoyed your photos and videos as well - particularly the time lapse version of the foxglove opening and closing. Amazing!


PegCole17 profile image

PegCole17 3 years ago from Dallas, Texas

Quite an interesting article between the balance of folklore and the scientific information here. What a beautiful flower that can be poisonous and yet helpful, too. I enjoyed learning more about the heart haven taken my Auntie for an ECHO cardiogram recently. They allowed me to stay in the room so I was able to watch the monitor and hear the heart beats. So cool.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you very much, drbj. Foxgloves and digitalis are fascinating topics. It's wonderful that a plant can be so useful, even if it may also be dangerous.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

It sounds like you had an interesting experience when you helped your Auntie, Peg. The heart is an interesting organ, in addition to being essential for life! Thanks for the visit.


bdegiulio profile image

bdegiulio 3 years ago from Massachusetts

Great hub Alicia. The foxglove is beautiful. I didn't realize it could be toxic? You continue to amaze me with your knowledge and ability to explain these things so that even I can understand. Did you ever teach? Well done. Voted up, shared, and pinned (love the photo and the top).


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Bill. Yes, I am a teacher. I teach high school students biology and other science subjects. Thank you for another kind comment and for the vote, the share and the pin!


rebeccamealey profile image

rebeccamealey 3 years ago from Northeastern Georgia, USA

I love foxglove. They are fantastic for container gardens and in border gardens. I hope I won't need to take it but it's nice to know it is an option regardless of side effects .Thanks for the info and the suggestion to use Digitalis under a doctor's supervision! Shared!


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Rebecca. I don't grow foxgloves, but there are a lot of wild ones near my home. Some people here like to keep the wild ones growing in their gardens when they find them there. It's important that no one self-medicates on foxglove or digitalis, but as you say, it's nice to know that doctors can prescribe a form of digitalis if it's necessary! Thank you very much for the share.


rose-the planner profile image

rose-the planner 3 years ago from Toronto, Ontario-Canada

Another insightful article about one of my favourite plants. You always produce great work! The benefits of the digitalis purpurea is amazing. Thank you for sharing. (Voted Up) -Rose


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you very much, Rose. I appreciate your comment and vote, as I always do!


RTalloni profile image

RTalloni 3 years ago from the short journey

Lots of important info on foxgloves here--interesting on every level. I enjoy learning from this type of hub, especially when it is so nicely done. Pinning to my Gardening: Flowers/Birds board.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thanks for the visit, the comment and the pin, RTalloni! I appreciate them all.


Sharkye11 profile image

Sharkye11 3 years ago from Oklahoma

Fascinating hub! I tried for years to grow foxglove. I never had any success and I quit trying when I had a baby.. They are still gorgeous flowers, and a very useful plant. Voting up!


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Sharkye11. Thank you very much for the comment and the vote! I wouldn't want foxgloves in my garden, since I have two dogs, but I enjoy seeing the plants in the wild and in landscaped areas. I've loved the flowers ever since childhood.


Deborah-Lynn profile image

Deborah-Lynn 3 years ago from Los Angeles, California

Wow, you took us from enjoying the beauty of Foxgloves, to an extremely helpful and easy to understand explanation of the medicinal applications of Foxgloves ' pharmaceudically significant applications, then to clear warnings about its' misuse. I really love your work, please alert me when you have similar publications on Facebook? Thanks, Deborah-Lynn


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Deborah-Lynn. Thank you for the visit. I appreciate your comment! It was nice to meet you on Facebook.


Eiddwen profile image

Eiddwen 3 years ago from Wales

A wonderful hub and thanks for sharing. Voting up and sharing onto my FB page A Brand New Dawn.

Enjoy your day.

Eddy.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you very much for the visit and the vote, Eddy! I appreciate your sharing the hub on your Facebook page, too.


toptengamer profile image

toptengamer 3 years ago from The Game

This is definitely one of my favorite flowers. We keep several gardens around the house and I'll definitely be adding foxglove to my list.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, toptengamer. It must be lovely to have several gardens! Foxglove would be a nice plant to grow. Thanks for the visit.


aviannovice profile image

aviannovice 3 years ago from Stillwater, OK

Remarkable how such a lovely plant can be so toxic, but many of them are. A good read with much knowledge imparted.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thanks for the comment, Deb. It is a shame that foxgloves are poisonous, but on the other hand it's great that they've given us a heart medicine!


Deborah-Lynn profile image

Deborah-Lynn 3 years ago from Los Angeles, California

Hi Alicia, I'm glad our paths crossed on FB also! I have another question about your Hub on Foxgloves. Do you have any information about how toxic these plants may be to pets? I have dogs that will literally dig up plant roots so I have to be careful where I locate my plants that can be harmful to animals. I just happened to see some at our local plant supplier but I decided to wait and ask you about that first.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Deborah-Lynn. I definitely wouldn't get foxgloves with a dog in the family! According to the ASPCA website, if a dog, cat or horse ingests foxglove, a poison control center should be contacted. ASPCA considers foxglove to be dangerous for dogs.


Faith Reaper profile image

Faith Reaper 3 years ago from southern USA

Hi AliciaC,

I written on the foxgloves too, as I found out that they were actually "Deadly Beauty" and your hub is most informative. I had purchased some foxgloves one time, and after I did so, a woman came up to me and asked me did I know they were poisonous, and I had no clue. She asked do you have small children around, and I do, my grandchildren! I thought, well, why do they have them all just sitting around? They need to have a warning on them! The ironic thing is that they use them in helping to cure breast cancer!

Excellent hub here. Voted up ++++ and sharing

Have a lovely rest of the weekend,

Faith Reaper


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Faith Reaper. I agree - plant stores should definitely warn people that foxgloves are poisonous! I've read about the very interesting John Hopkins research which showed that digitalis could slow the spread of certain types of cancer. I didn't include the information in my hub because I wanted to see the results of additional, more recent research, which I couldn't find. It would be wonderful if digitalis could help to fight cancer!

Thank you very much for the comment, the vote and the share, Faith. I hope that the rest of the weekend is wonderful for you, too!


lesliebyars profile image

lesliebyars 3 years ago from Alabama

I learned a lot that I didn't know until reading this hub!! Thanks for the insight!! I voted up and useful. I think Foxgloves are beautiful but, I had no idea they are poisonous.

Leslie


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, Leslie! Thanks for the visits and the votes. I think foxgloves are beautiful plants, too. They are lovely flowers, even if we have to be very careful with them!


DDE profile image

DDE 3 years ago from Dubrovnik, Croatia

Foxgloves - Beautiful Flowers and Digitalis Health Effects a beautiful flower and so incredibly effective to ones health. Voted up and beautiful


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thanks for the comment, DDE. Thank you for the votes, too - I appreciate them!


poetryman6969 profile image

poetryman6969 19 months ago

I think I prefer the "fairy glove" definition.

Fascinating information about digitalis.

Voted up.


AliciaC profile image

AliciaC 19 months ago from British Columbia, Canada Author

Thank you very much for the comment, poetryman. I like the fairy glove explanation, too!


adevwriting profile image

adevwriting 17 months ago from United Countries of the World

It was nice to know how digoxin works. I'm a heart patient and have to take it too. Interesting article!


AliciaC profile image

AliciaC 17 months ago from British Columbia, Canada Author

Thank you very much, adevwriting.

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