What substances can kill people?

Understanding Lethal Substances and Poisoning

Yes, numerous substances can kill people through poisoning, overdose, or toxic exposure, with opioids being the leading cause of poisoning deaths in the United States, accounting for over 75,000 deaths annually. 1

Epidemiology of Fatal Poisonings

In the 12-month period ending April 2021, more than 100,000 people in the United States died from poisoning and drug overdose, representing a 28.5% increase from the prior year, with 90% of these deaths being unintentional. 1

Leading Causes of Poisoning Deaths

Opioids:

• In 2013,16,235 people died from prescription opioid toxicity and an additional 8,257 died from heroin overdose in the United States. 1
• By 2017, drug overdose deaths exceeded 70,000, with opioids representing the majority. 1
• From 2019-2020, drug-related overdose rates among American Indians/Alaska Natives increased by 39%, surpassing all other racial groups. 1
• Opioid toxicity causes central nervous system and respiratory depression that progresses to respiratory and cardiac arrest if untreated. 1

Cocaine:

• In 84 of 107 cocaine-associated deaths (81%), no definitive cause was identified, leading investigators to hypothesize that myocardial infarction with ventricular fibrillation was the cause. 1
• Cocaine causes ventricular arrhythmias through sodium channel effects early after ingestion and through ischemia in delayed presentations. 1
• Cocaine prolongs the QT interval for several days after ingestion. 1

Acetaminophen:

• Acetaminophen was involved in 881 pharmaceutical overdose deaths in the United States in 2010. 1
• Acetaminophen can be hepatotoxic at dosages >3-4 grams/day and at lower dosages in patients with chronic alcohol use or liver disease. 1
• Studies from the United Kingdom demonstrated that increased access to paracetamol (acetaminophen) correlated with increased rates of attempted suicide and death by overdose. 1

Cyanide:

• Cyanide inhibits cellular respiration in mitochondria, causing rapid cardiovascular collapse, metabolic acidosis with elevated lactate, depressed mental status, seizures, and death. 1
• Cyanide is commonly liberated in structure fires from incomplete combustion of nitrogen-containing products like plastic, vinyl, wool, and silk. 1

Other Lethal Substances:

• NSAIDs were involved in 228 pharmaceutical overdose deaths in 2010, compared to 16,651 for opioid pain medications. 1
• Cardiac glycosides (digoxin) can cause life-threatening dysrhythmias. 1
• β-blockers and calcium channel blockers cause life-threatening hypotension and cardiac complications. 1
• Local anesthetics, particularly bupivacaine, can cause life-threatening toxicity. 1
• Tricyclic antidepressants cause serious arrhythmias including ventricular tachycardia, supraventricular tachycardia, and cardiac arrest. 1
• Pesticides (paraquat, dimethoate, fenthion) have been associated with suicide deaths, with studies showing decreased suicide rates after these substances were banned. 1

Critical Management Principles

For Opioid Overdose:

• Naloxone rapidly reverses CNS and respiratory depression with an excellent safety profile. 1
• Naloxone can be administered intravenously, intramuscularly, intranasally, or subcutaneously. 1
• First aid providers encountering suspected opioid overdose with unresponsiveness and absent/abnormal breathing should activate emergency response, provide high-quality CPR with compressions plus ventilation, and administer naloxone. 1

For Cocaine Toxicity:

• Standard advanced life support with sodium bicarbonate administration is appropriate for life-threatening dysrhythmias caused by cocaine or other sodium channel blockers. 1

For Cyanide Poisoning:

• If cyanide poisoning is suspected, do not wait for confirmatory testing—treat immediately with hydroxocobalamin (preferred) or sodium nitrite plus sodium thiosulfate. 1

For Cardiac Glycoside Poisoning:

• Digoxin-specific immune antibody fragments can reverse life-threatening dysrhythmias from digoxin poisoning. 1

Key Clinical Pitfall

The most common error is delaying antidote administration while waiting for confirmatory testing in suspected poisoning cases. 1 For substances like cyanide, opioids, and digoxin where specific antidotes exist with favorable safety profiles, immediate empiric treatment based on clinical suspicion is lifesaving. 1