title: Beta blocker toxicity after overdose: when do symptoms develop in adults?
abstract: Published reports of beta blocker ingestions in adults are retrospectively reviewed to determine at what point postingestion symptoms develop. Thirty-nine symptomatic beta blocker ingestions were found. The patients ranged from 14 to 67 years of age. Thirty-one (80%) of those who demonstrated symptoms did so within 2 h of ingestion. This number rose to thirty-eight (97%) by 4 h postingestion. Only one patient developed symptoms after more than 4 h of asymptomatic observation. The development of bradycardia and first degree atrioventricular block during observation appeared to predict toxicity in this patient who suddenly developed hypotension 6 h postingestion. No patient required treatment for delayed cardiovascular depression if they remained asymptomatic during a 4-h period of observation postingestion and demonstrated a normal electrocardiogram throughout. Whether the risk of delayed onset of toxicity after 6 h of asymptomatic observation is sufficiently low to warrant "medical clearance" requires further investigation.
authors.affiliation: Department of Emergency Medicine, Georgetown University Hospital, Washington, DC.
authors.forename: J N
authors.initials: JN
authors.lastname: Love
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000506:poisoning*; D000328:Adult; D062787:Drug Overdose; D004562:Electrocardiography; D006801:Humans; D013997:Time Factors
chemical_list: D000319:Adrenergic beta-Antagonists