Approach to Drug-Induced Bradycardia and Hypotension

5 main classes of drugs/toxins that induce bradycardia and hypotension (ABCDO)

  • Alpha-2 agonist
  • Beta-blockers
  • Calcium channel blockers
  • Digoxin and cardiac glycosides
  • Acetylcholinesterase inhibitors (Organophosphates)


Key Points:

  • Physical exam, labs, and ECG determine the class of drug/toxin. 
  • Ensure physical exam includes vitals (including RR) pupils, heart/lung exam, abdominal exam including bowel sounds, and peripheral pulses.
  • Obtain a blood glucose to differentiate beta blocker (hypoglycemia or normoglycemia) versus calcium channel blocker (hyperglycemia) toxicity. More labs detailed below. 


Alpha-2 Agonists

Beta Blockers

Calcium Channel Blockers

Digoxin and Cardiac Glycosides

Acetylcholinesterase Inhibitors