- Published on
Toxicology – Single-Dose Lethal Toxins
Clinicians should be aware that even a single dose of certain medications can be fatal, particularly in infants and children. The following are important high-risk agents and their mechanisms:
Alpha-2 Adrenergic Agonists (e.g., Clonidine)
These centrally acting agents can lead to significant central nervous system depression, bradycardia, hypotension, and respiratory depression.
Beta-Blockers (e.g., Propranolol)
Propranolol is especially dangerous due to its lipophilic nature, allowing central nervous system penetration. Toxicity may result in hypoglycemia, altered mental status, bradycardia, hypotension, heart block, and seizures.
Calcium Channel Blockers
These drugs impair cardiac conduction and contractility, causing bradycardia, hypotension, and heart block. Hyperglycemia may also occur due to reduced insulin release.
Sulfonylureas
These oral hypoglycemic agents can cause profound and prolonged hypoglycemia, leading to altered mental status, seizures, and coma.
Opioids (Narcotics)
Opioids, including heroin and prescription medications, can cause severe respiratory depression or arrest. Ingestion of transdermal patches is a particular risk in children.
Nicotine
Nicotine toxicity can produce cholinergic symptoms such as muscle fasciculations, along with cardiovascular and neurological effects.
Tricyclic Antidepressants (TCAs)
TCAs block cardiac sodium channels, resulting in conduction delays, widened QRS complexes, and potentially fatal arrhythmias.
Salicylates
Substances such as oil of wintergreen and certain bismuth-containing compounds disrupt oxidative phosphorylation, leading to metabolic acidosis, cerebral edema, pulmonary edema, seizures, and death.
Camphor
Camphor ingestion can rapidly cause nausea, vomiting, tachycardia, central nervous system depression, and seizures, especially in children.
Colchicine and Podophyllin
These agents disrupt microtubule formation, impairing cell division. Toxicity presents with gastrointestinal symptoms and can progress to hypotension and multisystem organ failure.
Acetylcholinesterase Inhibitors (AChEIs)
Medications used for Alzheimer disease can lead to a cholinergic toxidrome in overdose, with symptoms including bradycardia, bronchorrhea, and altered mental status.
Quinine and Quinidine
These agents block sodium channels, leading to cardiac conduction abnormalities such as QRS widening, QT prolongation, and potentially life-threatening arrhythmias.
49
Clinicians should be aware that even a single dose of certain medications can be fatal, particularly in infants and children. The following are important high-risk agents and their mechanisms:
Alpha-2 Adrenergic Agonists (e.g., Clonidine)
These centrally acting agents can lead to significant central nervous system depression, bradycardia, hypotension, and respiratory depression.
Beta-Blockers (e.g., Propranolol)
Propranolol is especially dangerous due to its lipophilic nature, allowing central nervous system penetration. Toxicity may result in hypoglycemia, altered mental status, bradycardia, hypotension, heart block, and seizures.
Calcium Channel Blockers
These drugs impair cardiac conduction and contractility, causing bradycardia, hypotension, and heart block. Hyperglycemia may also occur due to reduced insulin release.
Sulfonylureas
These oral hypoglycemic agents can cause profound and prolonged hypoglycemia, leading to altered mental status, seizures, and coma.
Opioids (Narcotics)
Opioids, including heroin and prescription medications, can cause severe respiratory depression or arrest. Ingestion of transdermal patches is a particular risk in children.
Nicotine
Nicotine toxicity can produce cholinergic symptoms such as muscle fasciculations, along with cardiovascular and neurological effects.
Tricyclic Antidepressants (TCAs)
TCAs block cardiac sodium channels, resulting in conduction delays, widened QRS complexes, and potentially fatal arrhythmias.
Salicylates
Substances such as oil of wintergreen and certain bismuth-containing compounds disrupt oxidative phosphorylation, leading to metabolic acidosis, cerebral edema, pulmonary edema, seizures, and death.
Camphor
Camphor ingestion can rapidly cause nausea, vomiting, tachycardia, central nervous system depression, and seizures, especially in children.
Colchicine and Podophyllin
These agents disrupt microtubule formation, impairing cell division. Toxicity presents with gastrointestinal symptoms and can progress to hypotension and multisystem organ failure.
Acetylcholinesterase Inhibitors (AChEIs)
Medications used for Alzheimer disease can lead to a cholinergic toxidrome in overdose, with symptoms including bradycardia, bronchorrhea, and altered mental status.
Quinine and Quinidine
These agents block sodium channels, leading to cardiac conduction abnormalities such as QRS widening, QT prolongation, and potentially life-threatening arrhythmias.
49
0 Comments
