Introduction to Foxglove (Digitalis Purpurea)
In the millennia that mankind has been on earth, uncounted millions of people have died from heart ailments. One type of malfunction is now called congestive heart failure, but once it was called dropsy. Some, but not all, of the symptoms of this problem are: fatigue, edema of the abdomen, legs and ankles, inability to sleep, shortness of breath, increased urination and nausea.
It is interesting that some medications are derived from plants that grow naturally in the environment. These medications can be called natural remedies, because they grow in nature and are also effective in treating ailments. One such plant is foxglove.
The foxglove plant is covered with large blossoms, often in shades of purple or pink. It is a beautiful plant that has some unusual characteristics, including being poisonous when it is eaten.
Foxglove is native to both western and eastern Europe, but it can now be found in all parts of the world. It grows in the wild, often in mountainous and forested areas and also along roadsides. While it grows in the wild, it is now also grown and harvested as a crop so it can be processed for medical purposes.
The History of Foxglove
Foxglove has been called by many different names in different times and at different places. Some of the more common names applied to foxglove include: deadmen’s bells, common foxglove, fairy’s glove, witch’s bell, purple foxglove, folk’s glove, virgin’s glove, bloody fingers and fairy’s caps. It can be noted that all of these names refer to the appearance, size, shape and color of the blossoms. People have long admired this plant because of its long, beautiful, purplish or pinkish bell-shaped blossoms that grow up and down long, slender stalks. The plants can be from three feet to six feet high. The fact that it is poisonous also tends to get people’s attention.
Modern medicine owes a great debt of gratitude to the early doctors and researchers who studied and learned the healing properties of so many herbal natural remedies, including foxglove. The first time that foxglove is mentioned in relation to being used as a medication was in the 13th century. It was first used and written about in Ireland and then later in Scotland. It was utilized in the attempt to treat a number of unrelated illnesses.
The credit for developing foxglove into an effective medication goes to Dr. William Withering. He was a British physician, who lived from 1741 to 1799. Dr. Withering became aware that people were using foxglove to treat what was then called dropsy and that it was an effective treatment for that condition. No one understood the “why” of the healing properties of this plant, so he made it his life’s work to discover why it worked and how to use foxglove more effectively. In 1785, he published his findings.
Dr. Withering discovered digitalis, an active ingredient in foxglove. After isolating and identifying this substance, he continued to study and learn the properties of this medication that has been such a boon to mankind. On a personal note, Dr. Withering was a genuinely good man. Each year, he treated 2000 to 3000 poor patients who could not afford to pay him. This limited his income to about 1000 British pounds per year, while his peers were earning about 5000 British pounds per year. After years of suffering from tuberculosis, he died in 1799 at the age of 58.
Myths that Relate to Foxglove
Foxglove has been associated with magic and mystery for centuries. Perhaps the fact that even though it is the source of a powerful, beneficial medication, it is also highly poisonous when eaten is a reason for the interest shown in it. One legend says that fairies used to give the blossoms to foxes to use as gloves.
This enabled them to move quietly, so they would not be caught stealing a farmer’s chickens. Connecting the foxglove flowers and foxes made sense, because foxgloves grow on the forested hillsides where foxes have their dens. Another story says that medieval witches cultivated foxglove to use as an ingredient in potions created to cast spells on people. These plants were sometimes grown in medieval gardens and dedicated to the Virgin Mary. Those were appropriately called “virgin’s glove.” Even today, some who practice paganism and similar religions use foxglove in some rituals.
Digitalis, Called Digoxin, Is Extracted from Foxglove
Digitalis, more often called digoxin, is a purified cardiac glycoside used to treat a variety of heart conditions, including: atrial fibrillation, atrial flutter and sometimes even heart failure. It can be effective when other medications are not. Lanoxin, Digitek and Lanoxicaps are names under which digoxin is commonly marketed.
It is usually administered by mouth but can be injected in critical situations. When conditions exist for digoxin to be used in the treatment process, myocardial efficiency improves, because hemodynamics and the ventricular function curve both improve. Digoxin is available only with a doctor’s prescription. It is primarily eliminated in the kidneys, so dosage must be reduced for those with a kidney problem.
Growing Digitalis Purpurea Commercially and Producing Digoxin
The process used today to produce digoxin is very similar to that used by Dr. Withering in the 18th century. Approximately 1000 kg of dried foxglove leaves are required to make 1 kg of pure digoxin. The process of extracting relatively small amounts of digoxin is not complicated, but it is expensive.
Commercial farming of foxglove to obtain digitalis in the USA began during World War II, when it was not possible to secure a sufficient amount from Europe. The plant grows best in the northern part of the United States and in Canada. At first, there was sufficient wild foxglove to meet the demand, but greater amounts than what could be harvested from plants growing wild were soon required.
Early efforts to grow foxglove commercially were unsuccessful. In the area where foxglove grows best, the roots of the plants had to be removed from the soil in the fall and stored through the winter. That was an expensive process. Also, the seeds of the foxglove plant are very small and sometimes are not viable.
The best method for growing foxglove plants involves the plants spending the first few weeks in a greenhouse. That is not economically feasible, because labor costs are so high in the United States. The result of all this is that, even now, most digitalis purpurea is imported.
Side Effects with the Use of Digoxin
In adults, every medicine can cause side effects, but no common side effects have been discovered due to usage of this drug. However, a person should seek medical help right away if he experiences a severe allergic reaction including: difficulty breathing, tightness in the chest, hives, fever, irregular heart beat or swelling in or around the mouth.
Digoxin and Children
Digoxin is also an effective medication for use in infants and children with slight to moderate congestive heart failure or irregular heartbeat due to atrial fibrillation. As with adults, dosage must be determined by careful clinical assessment of the individual and monitored carefully.
The daily dose for children should usually be divided, not given all at once in one dose. Once past the immediate newborn stage, children under 10 years of age usually need doses that are proportionally larger than those given to adults, but adjusted according to their body weight or surface area.
Children over 10 years of age need to be given adult dosages, but, again, the doses must be in proportion to the child’s body weight.
Pets Can Also Develop Congestive Heart Failure
Not only humans, but also their pets, can develop the symptoms of congestive heart failure. For the person who dearly loves his dog or cat and considers it part of the family, this is a vexing problem. When this kind of illness affects a dog or cat, it is for basically the same reasons that humans develop this disease.
The key to helping your pet is to take him to a veterinarian. The vet will use all the same techniques to diagnose and treat your furry little friend that are used with humans. If you want to learn more about congestive heart failure in animals, you can learn a lot by reading about heart disease in humans.
It may be encouraging to pet owners to know that the drugs used to treat pets are also approved by the FDA. It will be helpful financially if the pet owner has purchased pet health insurance before such a dire event occurs in his pet’s life.
What Should Treatment for Congestive Heart Failure Include Besides Medication?
The one who suffers from congestive heart failure should receive prescriptions for the proper medication, but there are other considerations to properly treat this condition. The first, and perhaps most important, is lifestyle modification. There are seemingly small changes that the patient must make. Sodium causes more fluids to accumulate in body tissue. Limiting the amount of both sodium and fluids consumed is very important. The slogan about drinking eight classes of water per day is certainly not intended for those suffering from congestive heart failure.
Aerobic exercise is now considered beneficial in helping a patient to function physically and have a higher quality of life. Sometime surgery is required to restore an adequate flow of blood through the heart. A doctor will often have other suggested changes for his patients’ lifestyle.
What Causes Congestive Heart Failure?
Congestive heart failure is an ailment in which the heart is unable to pump sufficient oxygen-rich blood to allow the body to function in a normal way. The condition can be caused by 1) diseases that increase a body’s demand for oxygen, 2) diseases that adversely affect the heart muscles, or 3) diseases that stiffen heart muscles. Any disease that inhibits the heart’s pumping by limiting the pumping action of the ventricles is a basic cause for congestive heart failure. Diseases such as hemochromatosis or amyloidosis can do that.
Users of Digoxin Can Experience Digoxin Toxicity
Physicians have long been aware of a potential problem that can arise when digoxin is prescribed. It is a complex reaction called “digoxin toxicity.” This syndrome was originally described by Dr. Withering in 1785. Approximately 0.4% of those admitted to hospitals, 1.1% of those not hospitalized, and 10 – 18% of nursing home residents who receive digoxin develop this toxicity.
In 2006, 2610 cases of toxic digitalis exposure were reported by the American Association of Poison Control Centers. The number of cases reported is declining because of increased awareness of dangerous drug interactions and for other reasons, including a decreased use of digoxin. Internationally, 2.17% of those on digoxin, who are hospitalized, develop digoxin toxicity.
The Cost of Digoxin
The national average cost of digoxin for a 250 mcg (0.25 mg) Tab is $7.00. Many people buy from online and Canadian pharmacies, as well as in local drugstores.
Tips for Helping Digoxin Work as Effectively as Possible
Here are some things the person who takes digoxin can do to help this medication work as effectively as possible:
- Some foods may prevent the absorption of digoxin. It is helpful to take this medicine either one hour before eating or two hours afterward.
- Do not take any new medicine, either prescription or over-the-counter, without checking with your doctor first. Many medicines should be avoided because of possible drug interaction.
- There is no standard amount of digoxin that should be prescribed. Your doctor will need to determine what amount is best based on body weight, other prescribed medicines and how well you respond to this drug.
- A patient should take digoxin at the same time each day and drink a full glass of water with it.
- It is important for the patient to keep all scheduled appointments, both with his doctor and for lab work.
- In the event of an accidental overdose of digoxin, emergency treatment must be sought immediately.
- If you miss a regular dose, do not take an extra dose to make up for it if it is less than 12 hours until time for your next dose.
The Danger of Drug Interactions
Other prescription drugs, such as verapamil, guanidine, itraconazole, spironolactone and indomethasin can increase digoxin levels. This brings the danger of toxicity. There are other drugs that can cause a serious slowing of heart rate when taken with digoxin.
On March 31, 2009, there was a major recall of Caraco brand digoxin. This Class 1 Recall was made, because tablets were made and sold that differed in size and in the amount of digoxin they contained.
About a month later, in late April of 2009, all digoxin pills with the Digitek brand name were found to contain twice as much digoxin as they should. There were lawsuits filed for personal injury and wrongful death against Mylan Pharmaceuticals as a result.
On May 11, 2009, there was still another recall of digoxin by a company that repackages Caraco tablets. There have been numerous other recalls of this product through the years. The person who takes this medication should try to stay abreast, as much as possible, with whatever recalls are taking place.
The Value of Digitalis
A quotation concerning this medication, found on the web page here, tells the extent of the value of digitalis:
“Digitalis” is without question the most valuable cardiac drug ever discovered and one of the most valuable drugs in the entire pharmacopoeia. The introduction of digitalis was one of the landmarks in the history of cardiac disease.”(1)
This quotation is written here exactly as it is found on the website. Even though the (1) implies a footnote to give the credit for the quotation, there is no such footnote or other reference given.