Calcium channel antagonists include: verapamil, diltiazem, amiodipine, felodipine, isradipine, nicardipine, nifedepine, nimodipine, nislodipine, bepridil and mibefradil
Initial evaluation:
(1) The severity of intoxication symptoms is graded from minimum to extreme.
(2) The amount of drug ingested and whether sustained-release or not.
(3) The presence or absence of co-ingestants (digoxin, other)
Clinical signs of poisoning:
(1) hypotension to shock
(2) bradycardia
(3) hemodynamic instability
(4) pulmonary edema with verapamil and amlodipine
(5) confusion, agitation, decreased level of consciousness
(6) hyperglycemia
(7) metabolic acidosis
If no or minimal symptoms:
(1) a single dose of activated charcoal is given
(2) the patient is monitored for 12 hours if not sustained-release preparation ingestion vs 24 hours if sustained-release preparation ingested.
If mild to moderate symptoms then the patient needs to be admitted:
(1) airway control
(2) bowel decontamination
(2a) perform gastric lavage if presents shortly after ingestion, with massive ingestion or if there are sustained release pills
(2b) if not sustained-release preparation, then single dose of activated charcoal
(2c) if sustained-release or unknown, then either (a) whole bowel irrigation with polyethylene glycol or (b) multiple doses of activated charcoal are given
(2d) aggressive decontamination is discontinued if bowel motility is decreased
(3) calcium infusion
(3a) if digoxin toxicity ruled out then give an intravenous calcium bolus
(3b) calcium infusion
(4) additional drugs
(4a) insulin and glucose
(4b) phosphodiesterase inhibitor (amrinone)
(4c) glucagon
(4d) adrenergic agents
(4e) atropine if likely to be responsive
If symptoms are severe or extreme, then the patient may require:
(1) cardiac pacing
(2) balloon pump
(3) extracorporeal bypass
