Differentials
Beta-blocker toxicity
SIGNS / SYMPTOMS
Hypotension, possible depressed mental status.
INVESTIGATIONS
ECG (slow ventricular rate, AV nodal blockade with associated dysrhythmias).
Blood glucose: hypoglycemia.
Calcium-channel blocker toxicity
SIGNS / SYMPTOMS
Hypotension, usually normal mental status.
INVESTIGATIONS
ECG (slow ventricular rate, AV nodal blockade with associated dysrhythmias).
Blood glucose: hyperglycemia.
Clonidine toxicity
SIGNS / SYMPTOMS
Hypotension, bradycardia, lethargy.
Occasionally responsive to naloxone.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Hypothermia
SIGNS / SYMPTOMS
Hypothermia, cool extremities, hypotension, ventricular dysrhythmias with rapid ventricular response.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Organophosphate poisoning
SIGNS / SYMPTOMS
Salivation, lacrimation, urination, and bronchorrhea.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Ischemic heart disease
SIGNS / SYMPTOMS
Hypotension, bradycardia, chest pain or discomfort, history of exertional dyspnea with angina or anginal equivalent.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Acute MI
SIGNS / SYMPTOMS
Chest discomfort and/or pain, dyspnea, vomiting, pain characteristic of cardiac etiology, bradycardia, hypotension.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Elevated intracranial pressure
SIGNS / SYMPTOMS
Altered mental status, hypertension, sinus bradycardia (but could possibly have other bradycardic rhythms).
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Hyperkalemia
SIGNS / SYMPTOMS
Patients with hyperkalemia due to other etiologies (e.g., diminished potassium excretion, excessive endogenous potassium load, pseudohyperkalemia, redistribution from within cells into plasma) are typically awake and not lethargic.
Patients with chronic renal insufficiency may present with lethargy and with any number of other nonspecific complaints. Patients with hyperkalemia may also present as completely asymptomatic.
INVESTIGATIONS
Normal or therapeutic serum digoxin concentration.
Hypothyroidism
SIGNS / SYMPTOMS
Cold intolerance, fatigue, depression, thinning of hair, lethargy, or abnormal menstrual cycle.
INVESTIGATIONS
Elevated TSH and decreased T4 levels are useful in the diagnosis.
Use of this content is subject to our disclaimer