Digitalis toxicity
Digitalis is a medicine that is used to treat certain heart conditions. Digitalis toxicity is a complication of digitalis therapy. It may occur when someone takes too much of the drug at one time. (This is called an acute ingestion, or overdose.) It can also occur when levels of the drug build up for other reasons.
The most common prescription form of this medicine is called digoxin. Digitoxin is another form of digitalis.
Causes
Digitalis toxicity can be caused by high levels of digitalis in the body. A decreased tolerance to the drug can also cause digitalis toxicity. People with decreased tolerance may have a normal level of digitalis in their blood. They may develop digitalis toxicity if they have other risk factors.
People with heart failure who take digoxin are commonly given medicines called diuretics, which remove excess fluid from the body. Many diuretics can cause potassium loss. A low level of potassium in the body increase the risk of digitalis toxicity. Digitalis toxicity may also develop in people who take digoxin and have a low level of magnesium in their body.
Heart failure
Heart failure is a condition in which the heart is no longer able to pump oxygen-rich blood to the rest of the body efficiently. This causes symptom...
You are more likely to have this condition if you take digoxin, digitoxin, or other digitalis medicines along with drugs that interact with it. Some of these drugs are quinidine, flecainide, verapamil, and amiodarone.
If your kidneys do not work well, digitalis can build up in your body rather than be removed normally through urine. Any problem that affects how your kidneys work (including dehydration ) makes digitalis toxicity more likely.
Dehydration
Dehydration occurs when your body does not have as much water and fluids as it should. Dehydration can be mild, moderate, or severe, based on how muc...
Some plants contain chemicals that can cause symptoms similar to digitalis toxicity if they are eaten. Three of these are plants are foxglove, oleander, and lily of the valley.
Symptoms
These are symptoms of digitalis toxicity:
- Confusion
- Irregular pulse
-
Loss of appetite
Loss of appetite
A decreased appetite is when your desire to eat is reduced. The medical term for a loss of appetite is anorexia.
-
Nausea
,
vomiting
, diarrhea
Nausea
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
-
Fast heartbeat
Fast heartbeat
Palpitations are feelings or sensations that your heart is pounding or racing. They can be felt in your chest, throat, or neck. You may:Have an unpl...
-
Vision changes
(unusual), including blind spots, blurred vision, changes in how colors look, or seeing spots)
Vision changes
There are many types of eye problems and vision disturbances, such as: HalosBlurred vision (the loss of sharpness of vision and the inability to see ...
Other symptoms may include:
-
Decreased consciousness
Decreased consciousness
Decreased alertness is a state of reduced awareness. A coma is a state of decreased alertness from which a person cannot be awakened. A long-term co...
-
Decreased urine output
Decreased urine output
Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups)....
-
Difficulty breathing when lying down
Difficulty breathing when lying down
Breathing difficulty while lying down is an abnormal condition in which a person must keep the head raised by sitting or standing to be able to breat...
-
Excessive nighttime urination
Excessive nighttime urination
Normally, the amount of urine your body produces decreases at night. This allows most people to sleep 6 to 8 hours without having to urinate. Some p...
-
Overall swelling
Overall swelling
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
Exams and Tests
Your health care provider will examine you.
Your heart rate may be rapid, or slow and irregular.
An ECG is done to check for irregular heartbeats.
ECG
An electrocardiogram (ECG) is a test that records the electrical activity of the heart.
Blood tests that will be done include:
- Blood chemistry
-
Kidney function tests, including
BUN
and
creatinine
BUN
BUN stands for blood urea nitrogen. Urea nitrogen is what forms when protein breaks down. A test can be done to measure the amount of urea nitrogen ...
Creatinine
The creatinine blood test measures the level of creatinine in the blood. This test is done to see how well your kidneys are working. Creatinine can ...
-
Digitoxin and
digoxin test
to check levels
Digoxin test
A digoxin test checks how much digoxin you have in your blood. Digoxin is a type of medicine called a cardiac glycoside. It is used to treat certai...
- Potassium level
- Magnesium level
Treatment
If the person has stopped breathing, call 911 or your local emergency number, then start CPR .
CPR
CPR stands for cardiopulmonary resuscitation. It is an emergency lifesaving procedure that is done when someone's breathing or heartbeat has stopped...
If the person is having trouble breathing, call 911 or your local emergency number.
At the hospital, symptoms will be treated as appropriate.
Digitoxin blood level may be lowered with repeated doses of charcoal, given after gastric lavage .
Gastric lavage
Gastric suction is a procedure to empty the contents of your stomach.
Methods to cause vomiting are usually not done because vomiting can worsen slow heart rhythms.
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
In severe cases, medicines called digoxin-specific antibodies may be prescribed. Dialysis may be needed to reduce the level of digitalis in the body.
Antibodies
An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples of antigens include micr...
Outlook (Prognosis)
How well a person does depends on the severity of the toxicity and if it has caused an irregular heart rhythm.
Possible Complications
-
Irregular heart rhythms
, which may be deadly
Irregular heart rhythms
An arrhythmia is a disorder of the heart rate (pulse) or heart rhythm. The heart can beat too fast (tachycardia), too slow (bradycardia), or irregul...
-
Heart failure
Heart failure
Heart failure is a condition in which the heart is no longer able to pump oxygen-rich blood to the rest of the body efficiently. This causes symptom...
When to Contact a Medical Professional
Call your provider if you are taking a digitalis medicine and you have symptoms of toxicity.
Prevention
If you take digitalis medicine, you should have your blood level checked regularly. Blood tests should also be done to check for conditions that make this toxicity more common.
Blood tests
A comprehensive metabolic panel is a group of blood tests. They provide an overall picture of your body's chemical balance and metabolism. Metaboli...
Potassium supplements may be prescribed if you take diuretics and digitalis together. A potassium-sparing diuretic may also be prescribed.
References
Bain BJ, Nelson LS, Ford MD. Acute poisoning. In: Goldman L, Schafer AI, eds. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 110.
Cole JB, Roberts DJ. Cardiovascular drugs. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 152.
Goldberger AL, Goldberger ZD, Shvilkin A. Digitalis toxicity. In: Goldberger AL, ed. Clinical Electrocardiography : A Simplified Approach, 8th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 18.
Zeringue M, Fowler GC. Gastrointestinal decontamination. In: Pfenninger JL, Fowler GC, eds. Pfenninger and Fowler's Procedures for Primary Care . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2011:chap 202.
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Foxglove (Digitalis purpurea) - illustration
Foxglove (Digitalis purpurea) is a common garden plant that contains digitalis and other cardiac glycosides. These chemicals affect the heart. Foxglove is poisonous, although recorded poisonings from this plant are very rare.
Foxglove (Digitalis purpurea)
illustration
-
Foxglove (Digitalis purpurea) - illustration
Foxglove (Digitalis purpurea) is a common garden plant that contains digitalis and other cardiac glycosides. These chemicals affect the heart. Foxglove is poisonous, although recorded poisonings from this plant are very rare.
Foxglove (Digitalis purpurea)
illustration
Review Date: 4/20/2015
Reviewed By: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.