From the Guidelines
Digoxin toxicity is characterized by severe bradycardia, life-threatening arrhythmias, and high degrees of AV nodal blockade, among other symptoms. The symptoms of digoxin toxicity can be diverse, affecting multiple body systems. According to the 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care 1, common cardiac manifestations include severe bradycardia and life-threatening arrhythmias, such as ventricular tachycardia, ventricular fibrillation, and high degrees of AV nodal blockade.
Some key points to consider in digoxin toxicity include:
- Hyperkalemia is a marker of severity in acute cardiac glycoside poisoning and is associated with poor prognosis 1.
- Antidigoxin Fab antibodies should be administered to patients with severe life-threatening cardiac glycoside toxicity, with the dose depending on the ingested dose of digoxin, serum digoxin concentration, and weight of the patient 1.
- In critical cases, empiric administration of 10 to 20 vials of antidigoxin Fab may be necessary before a serum digoxin level can be obtained or in cases of life-threatening toxicity due to cardiac glycosides 1.
It is essential to promptly recognize digoxin toxicity, as severe cases can be life-threatening, requiring immediate discontinuation of the drug and possibly administration of antidigoxin Fab antibodies in severe cases. Elderly patients and those with renal impairment are at higher risk for developing toxicity, even at therapeutic doses. The administration of antidigoxin Fab antibodies is a critical component of treatment for severe digoxin toxicity, and its use is supported by the guidelines 1.
From the FDA Drug Label
In this trial, the most common manifestations of digoxin toxicity included gastrointestinal and cardiac disturbances; CNS manifestations were less common. High doses of digoxin may produce a variety of rhythm disturbances, such as first-degree, second-degree (Wenckebach), or third-degree heart block (including asystole); atrial tachycardia with block; AV dissociation; accelerated junctional (nodal) rhythm; unifocal or multiform ventricular premature contractions (especially bigeminy or trigeminy); ventricular tachycardia; and ventricular fibrillation. Digoxin may cause anorexia, nausea, vomiting, and diarrhea Rarely, the use of digoxin has been associated with abdominal pain, intestinal ischemia, and hemorrhagic necrosis of the intestines. Digoxin can produce visual disturbances (blurred or yellow vision), headache, weakness, dizziness, apathy, confusion, and mental disturbances (such as anxiety, depression, delirium, and hallucination) The earliest and most frequent manifestation of excessive dosing with digoxin in infants and children is the appearance of cardiac arrhythmias, including sinus bradycardia.
The symptoms of digoxin toxicity include:
- Gastrointestinal disturbances: anorexia, nausea, vomiting, diarrhea, abdominal pain, intestinal ischemia, and hemorrhagic necrosis of the intestines
- Cardiac disturbances:
- Rhythm disturbances: first-degree, second-degree (Wenckebach), or third-degree heart block (including asystole); atrial tachycardia with block; AV dissociation; accelerated junctional (nodal) rhythm; unifocal or multiform ventricular premature contractions (especially bigeminy or trigeminy); ventricular tachycardia; and ventricular fibrillation
- Cardiac arrhythmias: sinus bradycardia, conduction disturbances, supraventricular tachyarrhythmias, atrial tachycardia (with or without block), junctional (nodal) tachycardia, ventricular arrhythmias
- CNS manifestations: visual disturbances (blurred or yellow vision), headache, weakness, dizziness, apathy, confusion, and mental disturbances (such as anxiety, depression, delirium, and hallucination) 2
From the Research
Symptoms of Digoxin Toxicity
The symptoms of digoxin toxicity can be varied and affect multiple systems of the body. Some of the common symptoms include:
- Nausea and vomiting 3, 4, 5, 6, 7
- Cardiac arrhythmias, which can range from mild to severe and potentially life-threatening 3, 4, 7
- Hyperkalaemia, a condition characterized by elevated potassium levels in the blood 3
- Confusion and neurological symptoms 4, 6, 7
- Visual disturbances, including blurred vision, photopsia, dyschromatopsia, and color vision changes 5, 6
- Gastrointestinal symptoms, such as diffuse abdominal pain and dysphagia 5, 6
- Proprioceptive illusions, which can affect a person's sense of body position and movement 6
Severity of Symptoms
The severity of digoxin toxicity symptoms can vary widely, depending on factors such as the amount of digoxin ingested, the duration of exposure, and individual patient characteristics. In severe cases, digoxin toxicity can lead to life-threatening complications, including:
Diagnosis and Treatment
Diagnosis of digoxin toxicity is typically based on a combination of clinical presentation, laboratory tests, and electrocardiogram (ECG) findings. Treatment may involve:
- Reduction of digoxin absorption and prevention of hypokalaemia and hyperkalaemia 3
- Correction of cardiac arrhythmias and management of electrolyte disturbances 3, 4
- Administration of digoxin-specific antibody fragments in severe cases 3, 7
- Supportive care, including monitoring and management of symptoms, as well as treatment of any underlying conditions 4, 6, 7