Introduction
Digoxin, also known as Digitalis, is commonly prescribed to treat various heart conditions including heart failure. It belongs to a class of drugs known as cardiac glycosides. The way cardiac glycosides work is that they strengthen the contractions of the heart muscle and regulate its rhythm.
In this comprehensive guide, we will learn about the composition, uses, recommended dosage, potential side effects, and address some frequently asked questions about digoxin.
Composition
The active ingredient in digoxin is derived from the leaves of the Digitalis purpurea plant.
Mode of Action
Digoxin or Digitalis exerts its effects on the heart by inhibiting an enzyme in the cell membrane called the sodium-potassium ATPase pump. This pump is supposed to maintain a balance between the number of ions like sodium and potassium ions inside and outside the cells (particularly the heart cells). Digoxin inhibits this sodium-potassium ATPase pump, digoxin increases the concentration of calcium inside the cells. Calcium causes the contraction of the muscle. Thus digoxin leads to enhanced contractility and a more coordinated heart rhythm.
Uses
Digoxin is used to treat a number of heart diseases some of which include
- Heart Failure:
Digoxin is commonly prescribed for the treatment of heart failure. It helps the heart pump blood more effectively. This increased contractility of the heart also improves symptoms such as shortness of breath and fatigue and reduces the risk of hospitalization due to such symptoms.
- Atrial Fibrillation:
Atrial fibrillation, also called Afib, is a disorder of heart rhythm which is characterized by irregular and rapid heartbeats (tachycardia). Digoxin can control the heart rate in individuals with atrial fibrillation because it helps to restore a more normal heart rhythm thus preventing the risk of stroke.
- Supraventricular Tachycardia:
Supraventricular tachycardia (SVT) is another rapid heart rhythm of the upper chambers of the heart, the ventricles. Digoxin can be used to slow down the heart rate during SVT episodes. It slows electrical conduction in the atrioventricular node, therefore, decreasing the heart rate.
- Pediatric Heart Conditions:
Digoxin is also used in the treatment of heart disorders in children, such as congenital heart defects or heart failure. Digoxin improves the strength and efficiency of the heart of neonates with congenital heart diseases or controls the rate and rhythm of the heartbeat. This leads to improved blood circulation in the body.
- Hypertrophic Cardiomyopathy:
Digoxin may be prescribed to individuals with hypertrophic cardiomyopathy. In this condition, the heart muscle called the myocardium gets hypertrophied because of gene mutations (changes in genes). This condition is characterized by symptoms such as chest pain, especially during activity, fatigue, fluttering or pounding feeling in the chest, heart murmur, lightheadedness or dizziness, fainting, and shortness of breath, especially during activity. It can improve exercise tolerance in these patients.
Recommended Dosage
The dose of digoxin varies from patient to patient.
For heart failure or atrial fibrillation
Oral solution
- Adults, teenagers, and children 10 years and older:
The amount you take depends on your age, weight, and medical condition. Your doctor will decide the right dose for you. The therapy starts with 10 to 15 micrograms (mcg) for every kilogram (kg) of body weight.
The maintenance dose is 3 to 4.5 mcg per kg of body weight per day.
- Children 5 to 10 years old:
The amount you take depends on your age, weight, and medical condition. Your doctor will determine the right dose for you. The therapy starts with 20 to 35 micrograms (mcg) for every kilogram (kg) of your body weight.
The maintenance dose is 5.6 to 11.3 mcg per kg of body weight per day.
- Children 2 to 5 years old:
The amount you take depends on your age, weight, and medical condition. The therapy starts with 30 to 45 micrograms (mcg) for every kilogram (kg) of your body weight.
The maintenance dose is 9.4 to 13.1 mcg per kg of body weight per day.
- Infants 1 month to 24 months old:
The therapy starts with 35 to 60 micrograms (mcg) for every kilogram (kg) of your body weight.
The maintenance dose is 11.3 to 18.8 mcg per kg of body weight per day.
- Full-term babies:
The therapy usually starts with 25 to 35 micrograms (mcg) for every kilogram (kg) of your body weight.
The maintenance dose is 7.5 to 11.3 mcg per kg of body weight per day.
- Premature babies:
The therapy usually starts with 20 to 30 micrograms (mcg) for every kilogram (kg) of your body weight.
The maintenance dose is 4.7 to 7.8 mcg per kg of body weight per day.
Tablet Form
Adults:
You may receive the first few doses through an IV (rapid digitalization). After that, you can switch to oral tablets for maintenance therapy. The maintenance dose will be 0.125 to 0.5 milligrams (mg) once a day, depending on your body weight and medical condition.
Teenagers and children older than 10 years old: The dose you take will depend on your body weight and must be determined by your doctor.
Children younger than 10 years old:
The use and dose should be determined by your doctor.
Potential Side Effects
Digoxin can cause the following side effects in some people:
- Gastrointestinal Disturbances:
Common side effects of digoxin include nausea, vomiting, and diarrhea. These symptoms usually subside with continued use, but if they persist or worsen, medical attention should be sought.
- Cardiac Arrhythmias:
In some cases, digoxin can cause abnormal heart rhythms, including bradycardia (slow heart rate) or atrial or ventricular arrhythmias. If you experience palpitations, dizziness, or fainting, it is important to seek immediate medical attention.
- Visual Disturbances:
Digoxin may cause visual changes such as blurred or yellow-tinted vision. If any changes in vision occur, it is crucial to consult a healthcare professional.
- Electrolyte Imbalance:
Digoxin can affect the balance of electrolytes in the body, particularly potassium and magnesium. Low levels of these electrolytes can increase the risk of digoxin toxicity. Regular monitoring of electrolyte levels and appropriate supplementation may be necessary.
- Drug Interactions:
In addition to medication interactions, digoxin can also interact with certain substances, such as alcohol and tobacco. It is advisable to avoid excessive alcohol consumption and consult a healthcare provider regarding tobacco use while taking digoxin.
- Hypersensitivity Reactions:
Some individuals may experience allergic reactions to digoxin, including skin rashes, itching, or swelling. If any signs of an allergic reaction occur, you must seek immediate medical attention.
- Other Potential Side Effects:
Headache, confusion, rash, or changes in mood are a few other side effects some people have reported after taking digoxin. It is important to report any unusual symptoms to the healthcare provider.
Frequently Asked Questions
Can I take digoxin with other medications?
No, it is recommended to use Digoxin with other medications as advised by the doctor. Digoxin may interact with other medications, such as diuretics, beta-blockers, calcium channel blockers, and some antibiotics. Hence, it is important to inform your healthcare provider about all the medications or supplements you are currently taking to avoid drug interactions.
What should I do if I miss a dose of digoxin?
If you forget to take a dose of digoxin, take it as soon as you remember unless it is close to the time for the next scheduled dose. Do not double the dose to make up for a missed one.
Can digoxin be used during pregnancy or while breastfeeding?
The use of digoxin during pregnancy or while breastfeeding should be discussed with a healthcare provider. Digoxin can be prescribed to a pregnant lady if the benefits of this medicine outweigh the risks. But careful monitoring is necessary to ensure the safety of both the mother and the baby.
Can digoxin interact with herbal supplements?
Yes, digoxin can potentially interact with certain herbal supplements, such as St. John’s Wort, ginseng, and hawthorn. You must inform your doctor about any medicine or herbal remedies you are using as it can help save you from any potential interactions.
How long does it take for digoxin to start working?
The onset of action of digoxin can vary among individuals. It typically takes a few hours to start exerting its effects on the heart. However, the full therapeutic benefits may not be seen for several days or weeks. You must take your medicine according to the doctor’s advice. Follow up with your healthcare provider for monitoring and dosage adjustments.
Conclusion
Digoxin is a commonly prescribed medication that is used to treat different heart conditions like heart failure, atrial fibrillation, and supraventricular tachycardia. It is an important medication as it helps improve heart function and maintain a steady heart rhythm. To ensure the best results and your safety, it is crucial to follow the recommended dosage provided by your healthcare provider. Additionally, it is important to be aware of any potential side effects and to regularly communicate with your healthcare provider about your treatment. If you notice any worrisome symptoms or if you have any questions about your medication, it is essential to promptly consult your healthcare provider for guidance and assistance. Their expertise will help ensure that you receive appropriate care and achieve the most effective outcomes.