Digoxin (Oral)

Overview

Digoxin is a drug extracted from the foxglove plant (digitalis lanata), which is used to treat heart failure as well as certain types of heart rhythmic disorders such as chronic atrial fibrillation. It is often prescribed with other medications such as water pills or angiotensin converting enzyme (ACE) inhibitors, to help improve its effectiveness. Digoxin is a form of cardiac glycoside and works by affecting the levels of minerals that exist in the cells of the heart, such as sodium and potassium. The levels of these minerals help it to maintain a strong and steady heartbeat, and thereby reduces strain on the heart.

The amount of digoxin that is useful to patients is very close to a toxic amount of the drug. Therefore patients should be careful when using digoxin, particularly if they have been prescribed a solution form of the medicine.

Young children may be particularly sensitive to this medication. Parents and caretakers of children who have been prescribed digoxin should monitor them carefully to check for any adverse reactions.

Digoxin is prescribed to help patients maintain their ability to exercise and carry out daily activities. In the case of irregular heartbeats, treatment can mean a decrease in the risk of blood clots, which in turn reduces heart attack or stroke risks. The use of digoxin also helps to improve blood circulation, which lessens swelling in the hands and ankles of patients with heart problems.

There are several drugs and products that interact with digoxin. Patients should avoid foods high in fibre while on digoxin for instance, or if they are unsure about what foods to take, they should consult their doctors about their nutritional issues. Marijuana and alcohol especially may interact with digoxin to produce unwanted effects, and patients who use them regularly should refrain from them during the course of treatment. Common supplements and drugs that may interact with digoxin include diuretics, or water pills, as well as vitamin C or vitamin B12.

Digoxin is currently only available via a doctor's prescription. It is available in a few forms, namely as tablets, in solution form, as liquid-filled capsules or as elixirs.

Conditions Treated

  • Heart failure

Type Of Medicine

  • Cardiac glycoside

Side Effects

Some side effects may occur during treatment with digoxin. Not all patients will encounter such side effects. However patients should still look out for any unusual symptoms, and they should contact their doctor as soon as possible if they experience such symptoms. The following is an incomplete list of side effects; if the patient encounters any side effect that is not covered here, they should also notify their doctor.

  • Rashes with lesions on skin

When using digoxin, some serious but rare side effects may occur, which will require immediate medical attention. They include:

  • Changes in mood

Some side effects are less severe and should go away after a while. The patient should seek medical advice, however, if they persist or deteriorate, or if they have any further questions.

  • Headache

It is rare that an allergic reaction will happen with digoxin, but patients should still be alert for the following signs:

  • Rashes or itching of the skin

Dosage

Each patient's dosage will vary according to their individual needs, so they should follow their doctor's prescription closely. The following is an average dose for heart failure or atrial fibrillation; if the patient's dosage differs, they should not change their dose or schedule without consulting their doctor.

For oral dosage (solution):

  • For adults, teenagers, and children aged 10 and above: The doctor will determine the patient's dosage based on their age, weight and condition. Initial dosage is usually 10 to 15 micrograms (mcg) per kilogram of the patient's weight and may be adjusted as required by the doctor. Maintenance dosage ranges from 3 to 4.5mcg per kilogram of body weight a day.

For oral dosage (tablets):

  • For adults: The first few doses will be administered via injection by the doctor, also known as rapid digitalization, before the medication is switched to tablets to be consumed orally for maintenance. Maintenance dosage will be between 0.125 and 0.5 milligrams (mg) per day, to be adjusted by the doctor if found necessary.

It is important that patients using digoxin consume the exact amount of medicine they have been prescribed. Patients taking the oral dosage in the form of a solution should use a marked measuring dropper that comes with the packaging of the medicine, or an oral syringe in order to make sure that they are getting an exact and accurate amount. Teaspoons and tablespoons used for food are not useful for measuring exact amounts of liquid.

If the patient misses a dose, they should take the dose as soon as they remember, within 12 hours of the scheduled dose. However, if they miss the 12-hour window or if it is too close to their next dose, they should skip the missed one and resume the dosing schedule as usual. If the patient has missed more than two doses, they should contact their doctor for further medical advice.

Digoxin is most effective when it is constantly present in the blood. Patients should take the medicine as it has been prescribed - not more or less, or at different intervals. They should not miss any doses. In order to help the heart work as normal, the patient should take the medicine exactly as directed even if they feel better.

Patients may take digoxin with or without food. However, foods that are high in fiber or certain medications may affect the rate of absorption of digoxin by the body. In these cases, the patient should consume the foods at least two hours before or after taking their medication. These include products such as:

  • Cholestyramine

The following products should be consumed as far from each dose of digoxin as possible.

  • Kaolin-pectin

Interactions

Drugs may interact with one another, or with supplements or herbal products, which may lead to a decrease in the effectiveness of the medicine or even to a higher risk of unwanted side effects. Certain drug interactions with digoxin may lead to a deterioration of a heart condition.

Before using digoxin, the patient should let their doctor or pharmacist know of any current medication, supplements or herbal products they are currently consuming. They should also let them know of any allergies they may have.

Even though some drugs may interact, the doctor may still decide to prescribe two or more medications together if they feel that it is necessary.

Certain medications and supplements may affect how quickly digoxin is removed from the body or the effectiveness of digoxin. These include:

  • St. John's wort

Common medications which interact with digoxin are listed as follows:

  • Acetaminophen

The above is not a complete list of medicines that may interact with digoxin. If patients wish to obtain more information, they may check with their doctor or pharmacist.

Certain medical problems may affect the effectiveness of digoxin. These medical problems may cause the patient to be more resistant to the medicine, or even cause an increased chance of digoxin toxicity, among other interactions that may occur. Prior to treatment, patients should share their medical history with their doctor so that their medicine can be adjusted if necessary. These include conditions such as:

  • Blood vessel disease (such as arteriovenous shunts)

If the patient has had an electrical cardioversion of atrial fibrillation, or is scheduled for one, they should inform their doctor as well. This is so that the dosage of digoxin can be adjusted accordingly one to two days before the procedure, or there may be a risk of worsening the patient's condition.

Alcohol, marijuana and tobacco are likely to interact with digoxin, and patients should refrain from consuming them during treatment. They should also consult with their doctor on what foods they should avoid or when they can consume them while using digoxin.

Warnings

Patients should not stop or change their dose of digoxin without first checking with their doctors, as sudden stops or changes may lead to serious alterations in the functioning of the heart. Doctors should also check the patient's progress regularly while they are on digoxin, to ensure that everything is progressing normally, and to check if a change in dose may be required. The patient may have to undergo blood tests to assess if there are any unwanted effects developing.

There is a strong possibility of overdosing on digoxin, especially if the patient is consuming the solution form of the medicine, which requires an accurate measurement of each dose. This is because the amount of medicine required for treatment is often close to amounts that cause an overdose. The patient should be alert for signs of digoxin overdose, which are listed as follows:

  • Confusion

Children and infants may be more sensitive to the effects of digoxin. They may not show symptoms as quickly as adults, with the exception of a change in the rate and rhythm of their heartbeat. Parents and caretakers should monitor their children's heart rates regularly while they are on digoxin.

Patients may be required to carry a medical identification card or a medical bracelet on them at all times, stating that they are currently using digoxin.

Prior to starting digoxin, patients should let their doctors know their medical history (such as kidney or thyroid problems, among others) and any allergies they may have. This is to prevent medical interactions, and allergic reactions to either the drug, other similar drugs, or inactive ingredients that the medicine may contain.

Digoxin may blur the vision or induce dizziness; the effects may be exacerbated by alcohol or marijuana. Patients should speak to their doctor if they are currently using marijuana, or drink alcohol frequently, and refrain from them. While on digoxin, they should avoid activities that require alertness or clear vision, such as driving or operating heavy machinery.

Certain medications such as diuretics, or 'water pills', may affect the balance of natural minerals that exist in the body such as calcium, magnesium or potassium. This, in turn, may affect how digoxin works. Patients who are using diuretics, or who have a medical history of mineral imbalances should notify their doctor before starting digoxin.

The doctor or qualified healthcare professionals should also know if the patient is on digoxin before having surgery, or medical procedures such as electrical cardioversion as this will affect the results of the surgery or procedures.

Pregnant or breastfeeding patients should discuss the risks and benefits of this medicine with their doctor before starting treatment. For pregnant patients, digoxin should only be used when necessary. So far, while digoxin passes into breast milk, there is insufficient information on its effects on nursing babies. Therefore, breastfeeding patients should consult with their doctor on whether to use digoxin.

Current studies do not show that digoxin might have limited usefulness with elderly patients. However, elderly patients may be more susceptible to age-related problems with the kidneys or heart, which may require more close monitoring by the doctor and possible adjustments in the dosage of digoxin.

While using digoxin, patients should not use any medication that has not been prescribed or approved by their doctor. This includes over the counter medicine, vitamin supplements and herbal products.

Storage

Digoxin should be stored in a cool and dry place, away from direct sunlight. It should not be exposed to freezing temperatures, nor should it be kept in a bathroom as it may be too humid. The medicine should be kept out of reach of children and animals.

Expired or unwanted medicine should be disposed of properly. If the patient is unsure of how to handle medical waste, they should consult their doctor or local waste management for instructions on how to properly discard their medication.

Summary

Digoxin is a drug extracted from the foxglove plant, which is used to treat heart problems, such as congestive heart failure or heart rhythmic disorders like chronic atrial fibrillation. It affects the levels of certain minerals that exist naturally in the heart, such as sodium and potassium, which in turn affect the heartbeat. Digoxin can be used to help effect a more normal and steady heartbeat.

The possibility of overdosing with digoxin is higher than with other medications, as there is a small difference between therapeutic and toxic amounts of the drug. Patients who are using digoxin should be careful to measure out their exact dose and to follow their prescribed dosage schedule closely. They should also monitor themselves closely to ensure that if they encounter any side effects, they are able to contact their doctor right away to seek medical advice.

It is important that patients let their doctors know of their medical history, as well as any medicinal products they are consuming at the moment, whether that includes other drugs, vitamin supplements or various herbal products, to avoid both drug and medical problem interactions. Certain drugs such as diuretics may affect the levels of minerals like sodium and potassium in the heart. Marijuana and alcohol especially should be avoided as they may interact adversely with digoxin. Patients should also take care to let their doctors or healthcare givers know that they are taking dioxin if they are scheduled to go into surgery or for a medical procedure, such as an electrical cardioversion.

Younger children or babies may be especially sensitive to the effects of digoxin. Their parents and caretakers should be vigilant in monitoring them for side effects, especially if there are changes to their heartbeat. Elderly patients are not expected to have difficulty with digoxin, but they may encounter an elevated chance of kidney or heart problems that are related to age.

Despite the risk of side effects, digoxin is prescribed by the doctor if they feel that the benefits of the medicine outweigh the negative effects. Digoxin is used to help patients maintain a normal and strong heartbeat, to help them carry out daily activities and exercise without worry, and also to help patients with irregular heartbeats lower their risk of blood clots and their related diseases.

Links

1. https: //www.mayoclinic.org/drugs-supplements/digoxin-oral-route/description/drg-20072646
2. https: //www.webmd.com/drugs/2/drug-4358/digoxin-oral/details
3. https: //reference.medscape.com/drug/lanoxin-digoxin-342432#0
4. http: //www.cvpharmacology.com/cardiostimulatory/digitalis

Digoxin treats heart problems by strengthening and improving heart efficiency, as well as heartbeat rhythm.

  • Atrial flutter
  • Atrial fibrillation
  • Various other heart problems
  • Red spots the size of pinpoints on skin
  • Severe stomach pain
  • Unusual bleeding or bruising
  • Bleeding gums
  • Blood in urine
  • Black, tarry, or bloody stools
  • Unusual tiredness or weakness
  • Trouble with breathing
  • Swelling of feet and/or lower legs
  • Change in heartbeat rhythm (slower/faster/irregular)
  • Loss of emotion or feeling
  • Anxiety
  • Sense of impending death
  • Changes in vision
  • Loss of vision
  • Blurred vision
  • Seeing double
  • Seeing overly bright lights or halos around lights
  • Swelling or tenderness of the breast/chest
  • Unusual weakness or tiredness
  • Nausea
  • Vomiting
  • Dizziness
  • Loss of appetite
  • Swelling of the face/tongue/throat
  • Severe dizziness
  • Trouble with breathing
  • For children aged 5 to 10 years old: The doctor will determine dosage based on the child's age, weight and condition. Initial dosage is about 20 to 35mcg per kilogram of body weight and may be adjusted as required by the doctor. Maintenance dosage ranges from 5.6mcg to 11.3mcg per kg of body weight, per day.
  • For children aged 2 to 5 years old: The doctor will determine dosage based on the child's age, weight and condition. Initial dosage is 30 to 45mcg per kg of body weight, to be adjusted as the doctor finds necessary. Maintenance dosage ranges from 9.4 to 13.1mcg per kg of body weight, per day.
  • For infants aged 1 to 24 months: The doctor will determine dosage based on the infant's age, weight and condition. Initial dosage is 35 to 60mcg per kg of body weight, to be adjusted as the doctor finds necessary. Maintenance dosage ranges from 11.3 to 18.8mcg per kg of body weight, per day.
  • For full-term babies: The doctor will determine dosage based on the infant's age, weight and condition. Initial dosage is 25 to 35mcg per kg of body weight, to be adjusted as the doctor finds necessary. Maintenance dosage ranges from 7.5 to 11.3mcg per kg of body weight, per day.
  • For premature babies: The doctor will determine dosage based on the infant's age, weight and condition. Initial dosage is 20 to 30mcg per kg of body weight, to be adjusted as the doctor finds necessary. Maintenance dosage ranges from 4.7 to 4.8mcg per kg of body weight, per day.
  • For teenagers and children aged 10 years and above: The doctor will determine dosage based on body weight and condition.
  • For children aged younger than 10 years: The doctor will determine the dose and use of depending on the child's age, weight and condition.
  • Colestipol
  • Psyllium
  • Milk of magnesia
  • Metoclopramide
  • Sulfasalazine
  • Aminosalycylic acid
  • Antacids
  • Azole antifungals (such as itraconazole)
  • Dronedarone
  • Lapatinib
  • Macrolide antibiotics (such as clarithromycin)
  • Propafenone
  • Rifampin
  • Apixaban
  • Amifampridine
  • Ascorbic acid (vitamin C)
  • Aspirin
  • Atorvastatin
  • Carvedilol
  • Cholecalciferol (vitamin D3)
  • Clopidogrel
  • Cyanocobalamin (vitamin B12)
  • Fish oil (omega-3 polyunsaturated fatty acids)
  • Fluticasone
  • Furosemide
  • Insulin glargine
  • Levothyroxine
  • Metoprolol
  • Rivaroxaban
  • Rosuvastatin
  • Tiotropium
  • Warfarin
  • Hypocalcemia (low levels of calcium in the blood)
  • Hypoxia (low levels of oxygen in the blood)
  • Thyroid problems
  • Heart disease and problems (such as amyloid heart disease, restrictive cardiomyopathy or sick sinus syndrome)
  • Hypercalcemia (high levels of calcium in the blood)
  • Hypokalemia (low levels of potassium in the blood)
  • Hypomagnesemia (low levels of magnesium in the blood)
  • Kidney disease or problems
  • Myocarditis
  • Ventricular fibrillation
  • Problems with vision
  • Nausea
  • Vomiting
  • Diarrhea
  • Loss of appetite
  • Changes in heartbeat (becoming faster/slower/irregular)
  • Feeling of pounding heartbeat in the chest
  • Fainting
Resources
Last Reviewed:
March 26, 2018
Last Updated:
April 27, 2018