Digoxin

What is Digoxin?

• Digoxin (Cardoxin; Digitek; Lanoxicaps; Lanoxin), is one of the cardiac (or digitalis) glycosides, a closely related group of drugs having in common specific effects on the myocardium.
• These drugs are found in a number of plants.
• Digoxin is extracted from the leaves of Digitalis lanata.
• The term “digitalis” is used to designate the whole group of glycosides.
• The glycosides are composed of 2 portions: a sugar and a cardenolide (hence “glycosides”).

Digoxin

Digoxin structure 2

What are the uses of this medicine?

Digoxin (Cardoxin; Digitek; Lanoxicaps; Lanoxin), is used for:

• Treatment of mild to moderate heart failure in adults.
• Increasing myocardial contractility in pediatric patients with heart failure.
• Control of resting ventricular rate in patients with chronic atrial fibrillation in adults.

How does this medicine work?

• Digitalis (dij" i tal' is), digoxin (di jox' in) and digitoxin (dij" i tox' in) are cardiac glycosides that enhance myocardial contractility, probably by increasing levels of myocardial cytosolic calcium because of inhibition of sodium-potassium ATPase.
• Originally derived from the purple foxglove flower (Digitalis purpurea), the cardiac glycosides have been used in clinical medicine for more than two centuries.
• Once used as first-line agents for congestive heart failure and atrial fibrillation, the cardiac glycosides have been replaced by agents that are better tolerated and have been shown to improve long term survival such as the ACE inhibitors and beta-blockers.

Who Should Not Use this medicine ?

This medicine cannot be used in patients with:

• Ventricular fibrillation
• Known hypersensitivity to digoxin

What drug interactions can this medicine cause?

• Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.

Be sure to mention any of the following:

• antacids, antibiotics, calcium, corticosteroids, diuretics ('water pills'), other medications for heart disease, thyroid medications, and vitamins.

Is this medicine FDA approved?

• Digoxin is in the cardiac glycoside family of medications.
• It was first isolated in 1930 from the foxglove plant, Digitalis lanata.
• It is on the World Health Organization's List of Essential Medicines.
• In 2020, it was the 237th most commonly prescribed medication in the United States, with more than 1 million prescriptions.

How should this medicine be used?

Recommended dosage:

Loading Dosing Regimen in Adults and Pediatric Patients:

• For adults and pediatric patients if a loading dosage is to be given, administer half the total loading dose initially, then ¼ the loading dose every 6 to 8 hours twice.

For adults and pediatric patients 5 to 10 years:

• 20 to 45 mcg/kg

Adults and pediatric patients over 10 years:

• 10 to 15 mcg/kg

Maintenance Dosing in Adults and Pediatric Patients Over 10 Years Old:

Adults and pediatric patients over 10 years:

• 3.4 to 5.1 mcg/kg/day

Maintenance Dosing in Pediatric Patients Less Than 10 Years Old: 5 years to 10 years:

• 3.2 to 6.4 mcg/kg/dose Twice daily.

The typical dose is 0.125 to 0.25 mg daily, but dosing is often individualized because of tolerance and effect.

Administration:

• Digoxin comes as a tablet, capsule, or pediatric elixir (liquid) to take by mouth.
• Digoxin is usually taken once a day.
• The pediatric elixir comes with a specially marked dropper for measuring the dose.
• It is important that you always take the same brand of digoxin.
• Different brands of digoxin have different amounts of active drug and your dose would need to be changed.
• Digoxin helps control your condition but will not cure it.
• Continue to take digoxin even if you feel well.
• Do not stop taking digoxin without talking to your doctor.

What are the dosage forms and brand names of this medicine?

This medicine is available in fallowing doasage form:

• As a tablet, capsule, or pediatric elixir (liquid)

This medicine is available in fallowing brand namesː

• Cardoxin; Digitek; Lanoxicaps; Lanoxin

What side effects can this medication cause?

The most common side effects of this medicine may include:

• Gastrointestinal: In addition to nausea and vomiting, the use of digoxin has been associated with abdominal pain, intestinal ischemia, and hemorrhagic necrosis of the intestines.
• CNS: Digoxin can cause headache, weakness, dizziness, apathy, confusion, and mental disturbances (such as anxiety, depression, delirium, and hallucination).
• Other: Gynecomastia has been occasionally observed following the prolonged use of digoxin.

Less common, but serious side effects may include:

• Cardiac arrhythmias
• Digoxin Toxicity

• Thrombocytopenia and maculopapular rash and other skin reactions have been rarely observed.

What special precautions should I follow?

• Advise patients that many drugs can interact with Digoxin Tablets. Instruct patients to inform their doctor and pharmacist if they are taking any over the counter medications, including herbal medication, or are started on a new prescription.
• Advise patients to contact their doctor or a health care professional if they experience nausea, vomiting, persistent diarrhea, confusion, weakness, or visual disturbances (including blurred vision, green-yellow color disturbances, halo effect) as these could be signs that the dose of Digoxin Tablets may be too high.
• Advise parents or caregivers that the symptoms of having too high Digoxin Tablets doses may be difficult to recognize in infants and pediatric patients. Symptoms such as weight loss, failure to thrive in infants, abdominal pain, and behavioral disturbances may be indications of digoxin toxicity.
• Instruct the patient to monitor and record their heart rate and blood pressure daily.
• Patients with Wolff-Parkinson-White syndrome who develop atrial fibrillation are at high risk of ventricular fibrillation.
• Digoxin Tablets may cause severe sinus bradycardia or sinoatrial block particularly in patients with pre-existing sinus node disease.
• Digoxin Tablets are not recommended in patients with acute myocardial infarction because digoxin may increase myocardial oxygen demand and lead to ischemia.
• It may be desirable to reduce the dose of or discontinue Digoxin Tablets for 1 to 2 days prior to electrical cardioversion of atrial fibrillation to avoid the induction of ventricular arrhythmias.
• Digoxin Tablets can precipitate vasoconstriction and may promote production of pro-inflammatory cytokines; therefore, avoid use in patients with myocarditis.
• Patients with heart failure associated with preserved left ventricular ejection fraction may experience decreased cardiac output with use of Digoxin Tablets. Digoxin Tablets should generally be avoided in these patients, although it has been used for ventricular rate control in the subgroup of patients with atrial fibrillation.
• Hypocalcemia can nullify the effects of digoxin in humans; thus, digoxin may be ineffective until serum calcium is restored to normal.

What to do in case of emergency/overdose?

Symptoms of overdosage may include:

In Adults:

• The most common signs and symptoms of digoxin toxicity are nausea, vomiting, anorexia, and fatigue.
• Extremely high serum concentrations produce hyperkalemia especially in patients with impaired renal function.
• Almost every type of cardiac arrhythmia has been associated with digoxin overdose and multiple rhythm disturbances in the same patient are common.
• Neurologic manifestations (e.g., dizziness, various CNS disturbances), fatigue, and malaise are very common.
• Visual manifestations may also occur with aberration in color vision (predominance of yellow green) the most frequent.
• Neurological and visual symptoms may persist after other signs of toxicity have resolved.
• In chronic toxicity, non-specific extra-cardiac symptoms, such as malaise and weakness, may predominate.

In Children:

• Frequent non-cardiac effects are similar to those observed in adults although nausea and vomiting are not seen frequently in infants and small pediatric patients.
• Other reported manifestations of overdose are weight loss in older age groups, failure to thrive in infants, abdominal pain caused by mesenteric artery ischemia, drowsiness, and behavioral disturbances including psychotic episodes.
• Arrhythmias and combinations of arrhythmias that occur in adult patients can also occur in pediatric patients although sinus tachycardia, supraventricular tachycardia, and rapid atrial fibrillation are seen less frequently in pediatric patients.
• Pediatric patients are more likely to develop A-V conduction disturbances, or sinus bradycardia.

Management of overdosage:

• In case of overdose, call the poison control helpline of your country. In the United States, call 1-800-222-1222.

• Overdose related information is also available online at poisonhelp.org/help.
• In the event that the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services. In the United States, call 911.
• If there is suspicion of toxicity, discontinue Digoxin Tablets and place the patient on a cardiac monitor.
• Correct factors such as electrolyte abnormalities, thyroid dysfunction, and concomitant medications.
• Correct hypokalemia by administering potassium so that serum potassium is maintained between 4.0 and 5.5 mmol/L.
• Potassium is usually administered orally, but when correction of the arrhythmia is urgent and serum potassium concentration is low, potassium may be administered by the intravenous route.
• Monitor electrocardiogram for any evidence of potassium toxicity (e.g., peaking of T waves) and to observe the effect on the arrhythmia.
• Avoid potassium salts in patients with bradycardia or heart block.
• Symptomatic arrhythmias may be treated with Digoxin Immune Fab.

Acute Overdose:

• Patients who have intentionally or accidently ingested massive doses of digoxin should receive activated charcoal orally or by nasogastric tube.
• In addition to cardiac monitoring, temporarily discontinue Digoxin Tablets until the adverse reaction resolves.
• In particular, correct hypokalemia and hypomagnesemia.
• Digoxin is not effectively removed from the body by dialysis because of its large extravascular volume of distribution.
• Life threatening arrhythmias (ventricular tachycardia, ventricular fibrillation, high degree A-V block, bradyarrhythmia, sinus arrest) or hyperkalemia requires administration of Digoxin Immune Fab.
• Bradycardia and heart block caused by digoxin are parasympathetically mediated and respond to atropine.
• A temporary cardiac pacemaker may also be used.
• Ventricular arrhythmias may respond to lidocaine or phenytoin.
• When a large amount of digoxin has been ingested, especially in patients with impaired renal function, hyperkalemia may be present due to release of potassium from skeletal muscle.
• In this case, treatment with Digoxin Immune Fab is indicated; an initial treatment with glucose and insulin may be needed if the hyperkalemia is life threatening.
• Once the adverse reaction has resolved, therapy with Digoxin Tablets may be reinstituted following a careful reassessment of dose.

Can this medicine be used in pregnancy?

• Experience with digoxin in pregnant women over several decades, based on published retrospective clinical studies and case reports, has not led to the identification of a drug associated risk of major birth defects, miscarriage or adverse maternal and fetal outcomes.
• Untreated underlying maternal conditions, such as heart failure and atrial fibrillation, during pregnancy pose a risk to the mother and fetus
• Digoxin has been shown to cross the placenta and is found in amniotic fluid. Monitor neonates for signs and symptoms of digoxin toxicity, including vomiting, and cardiac arrhythmias.
• Digoxin requirements may increase during pregnancy and decrease in the postpartum period. Monitor serum digoxin levels during pregnancy and the postpartum period.

Can this medicine be used in children?

• The safety and effectiveness of Digoxin Tablets in the control of ventricular rate in children with atrial fibrillation have not been established.
• The safety and effectiveness of Digoxin Tablets in the treatment of heart failure in children have not been established in adequate and well-controlled studies.

What are the active and inactive ingredients in this medicine?

Active ingredient:

• digoxin

Inactive ingredients:

• anhydrous lactose
• silicon dioxide
• starch, corn
• lactose monohydrate
• magnesium stearate

Who manufactures and distributes this medicine?

Distr. by:

• West-Ward Pharmaceuticals Corp.
• Eatontown, NJ

What should I know about storage and disposal of this medication?

• Store in a dry place at 20º to 25ºC (68º to 77ºF) and protect from light.
• Keep out of reach of children.
• Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure.

• Dailymed label info on Digoxin
• FDA Digoxin

Digoxin Resources
Latest articles Most recent articles Ongoing trials	Wikipedia

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