From the Guidelines
Shortness of breath (SOB) is a symptom of digoxin toxicity, which can occur due to the drug's effect on the heart and lungs, and is often accompanied by other symptoms such as nausea, vomiting, visual disturbances, confusion, and cardiac arrhythmias. Patients with digoxin toxicity may experience respiratory distress, and the most concerning cardiac manifestations include bradycardia, heart blocks, and potentially life-threatening ventricular arrhythmias 1. Digoxin toxicity occurs when serum levels exceed the therapeutic range (0.8-2.0 ng/mL), often due to decreased renal clearance, drug interactions, or accidental overdose.
Key Symptoms and Treatment
- Other symptoms that often accompany SOB include:
- Nausea
- Vomiting
- Visual disturbances (yellow-green halos around objects)
- Confusion
- Cardiac arrhythmias
- If digoxin toxicity is suspected, the medication should be immediately discontinued and serum levels checked.
- Treatment may include:
- Activated charcoal for recent ingestions
- Correction of electrolyte abnormalities (particularly potassium)
- Administration of digoxin-specific antibody fragments (Digibind or DigiFab) as recommended by the 2023 American Heart Association focused update on the management of patients with cardiac arrest or life-threatening toxicity due to poisoning 1
Patient Management
Patients with significant SOB may require supplemental oxygen and cardiac monitoring. Elderly patients and those with renal impairment are at higher risk for developing toxicity even at standard doses, so careful monitoring is essential in these populations. According to the 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death, treatment of digoxin toxicity is based on the severity, and in mild cases, discontinuing the medication, monitoring rhythm, and maintaining normal serum potassium may be sufficient 1. However, the most recent guideline from 2023 recommends administration of digoxin-specific antibody fragments (digoxin-Fab) for digoxin or digitoxin poisoning 1.
From the Research
Symptoms of Digoxin Toxicity
- The symptoms of digoxin toxicity include nausea, hyperkalaemia, cardiac arrhythmias, and cardiac arrest 2
- Cardiac glycosides have a narrow therapeutic window, and digitalis treatment can easily lead to symptoms of overdose, including disturbances of cardiac function and of the circulatory system, as well as gastrointestinal symptoms and CNS disturbances 3
- Shortness of breath (SOB) is not explicitly mentioned as a symptom of digoxin toxicity in the provided studies, but it can be inferred that it may occur as a result of cardiac arrhythmias and conduction disturbances, such as those observed in the case study of a 45-year-old patient who ingested 100 0.25 mg tablets of digoxin 3
Treatment of Digoxin Toxicity
- The treatment of digoxin toxicity focuses on reduction of digoxin absorption, prevention of hypokalaemia and hyperkalaemia, treatment of symptoms, and, in severe toxicity, administration of digoxin antibodies 2
- Digoxin-specific antibody fragments (digoxin-Fab) are widely regarded as a safe and effective treatment for the management of acute and chronic digoxin poisoning 4
- Plasma exchange (PEX) may be considered in cases of severe digoxin toxicity with acute kidney injury, as it can facilitate the removal of digoxin-DSA complexes and bypass renal excretion 5