Overview
Digoxin is a cardiac glycoside used to treat heart failure and atrial fibrillation. It increases intracellular calcium, improving cardiac contractility. Digoxin slows down the heart rate in atrial fibrillation and reduces symptoms of heart failure. It is available in oral and injectable forms, with a narrow therapeutic window requiring careful monitoring. Common side effects include nausea, vomiting, and visual disturbances. Digoxin has contraindications and precautions, and it can interact with other medications. Toxicity can occur with high blood levels, causing severe symptoms. Consult a healthcare professional for personalized information and guidance.
Treatment
Digoxin is used in the treatment of heart failure and atrial fibrillation. In heart failure, it improves symptoms, increases cardiac output, and reduces heart size. In atrial fibrillation, it controls the heart rate by slowing down electrical conduction. The dosage of digoxin is individualized based on factors such as age, kidney function, and other medications. Regular monitoring of digoxin levels is necessary to ensure effectiveness and prevent toxicity. Common side effects include nausea, vomiting, and visual disturbances. It is important to be aware of contraindications, drug interactions, and potential toxicity. Always follow the guidance of a healthcare professional.
Presentation
Introduction
- Cardiac glycosides, specifically digoxin, are a class of medications used in the treatment of heart conditions.
- Digoxin is widely used for heart failure and atrial fibrillation management.
Mechanism of Action
- Digoxin inhibits the sodium-potassium ATPase pump in cardiac cells.
- This inhibition leads to increased intracellular calcium levels, resulting in enhanced cardiac contractility.
Indications
- Digoxin is indicated for heart failure, particularly when accompanied by atrial fibrillation.
- It helps improve cardiac pumping ability and controls heart rate in these conditions.
Atrial Fibrillation
- Digoxin is commonly prescribed to control heart rate in atrial fibrillation patients.
- It slows down electrical conduction through the atrioventricular (AV) node, reducing the heart rate.
Heart Failure
- Digoxin improves symptoms and quality of life in heart failure patients.
- It increases cardiac output and reduces heart size, alleviating symptoms like fatigue, shortness of breath, and fluid retention.
Pharmacokinetics
- Digoxin is available in oral and injectable forms.
- After oral administration, it is well absorbed and can have a prolonged effect.
- Regular monitoring of blood levels is crucial due to its narrow therapeutic window.
Dosage and Monitoring
- The dosage of digoxin varies based on individual factors such as age, kidney function, and concomitant medications.
- Regular monitoring of digoxin levels ensures efficacy and prevents toxicity.
Side Effects
- Common side effects include nausea, vomiting, loss of appetite, and visual disturbances.
- Higher doses or toxicity can result in severe effects such as arrhythmias.
Contraindications and Precautions
- Digoxin is contraindicated in ventricular fibrillation and specific heart block conditions.
- Caution is necessary in patients with impaired kidney function, electrolyte imbalances, and hypothyroidism.
Drug Interactions
- Digoxin can interact with several medications, including diuretics, beta-blockers, calcium channel blockers, and certain antibiotics.
- Close monitoring and potential dosage adjustments are required when combining digoxin with other drugs.
Toxicity
- Digoxin toxicity can occur when blood levels exceed the therapeutic range.
- Symptoms include severe nausea, vomiting, confusion, visual changes, and arrhythmias.
- Prompt medical attention is crucial in cases of suspected digoxin toxicity.
| Snapshot |
| A 28-year-old man presents to the emergency room after ingesting an unknown amount of his grandfather’s digoxin medication. He reports feeling depressed and ingested a handful of the drug about 1 hour ago. Since then, he states having abdominal pain, nausea, and vomiting. He also discloses that his vision is becoming blurry with yellow halos around objects. He is found to have a K+ of 6.5 mEq/L. He is quickly administered activated charcoal, given the recent ingestion, and started on digoxin antibodies. (Digoxin poisoning) |
| Introduction |
| Druga cardiac glycoside derived from the foxglove plant, digitalis purpureaMechanism of action direct reversible inhibitor of Na+/K+-ATPase causing ↑ in intracellular Na+ and ↓ in intracellular K+indirectly inhibits Na+/Ca2+-exchanger the increased intracellular Na+ prevents expulsion of Ca2+ from the cell and increases intracellular Ca2+this results in↑ free Ca2+ ions ↑ inotropy and contractility ↑ vagal tone ↓ conduction through sinoatrial and atrioventricular nodes↓ heart rateClinical useheart failureleft ventricular dysfunctionatrial fibrillation |
| Toxicity |
| Druga cardiac glycoside derived from the foxglove plant, digitalis purpureaMechanism of action direct reversible inhibitor of Na+/K+-ATPase causing ↑ in intracellular Na+ and ↓ in intracellular K+indirectly inhibits Na+/Ca2+-exchanger the increased intracellular Na+ prevents expulsion of Ca2+ from the cell and increases intracellular Ca2+this results in↑ free Ca2+ ions ↑ inotropy and contractility ↑ vagal tone ↓ conduction through sinoatrial and atrioventricular nodes↓ heart rateClinical useheart failureleft ventricular dysfunction-atrial fibrillation |
Conclusion
- Digoxin, a cardiac glycoside, is an important medication in the management of heart failure and atrial fibrillation.
- Understanding its mechanism of action, indications, dosage, monitoring, and potential side effects is essential for safe and effective use.
- Consultation with a healthcare professional is advised for personalized information and guidance.
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