- Last edited on November 27, 2021
Introduction to Toxidromes
Primer
Toxidromes (portmanteau of toxic + syndrome) are a medical syndrome caused by a elevated levels of a substance in the body, and often secondary to a drug overdose or adverse drug reaction.
Approach
Physical Exam Comparison
Toxidromes on Physical Exam
HR/BP | RR | Temperature | Pupils | Bowel Sounds | Diaphoresis | |
---|---|---|---|---|---|---|
Anticholinergic | N | |||||
Cholinergic | N or | N | N | |||
Extrapyramidal Symptoms | N or | N or | N | N | N | N or |
Opioid | ||||||
Sedative-Hypnotic | N | |||||
Sympathomimetic | ||||||
Serotonin Syndrome | ||||||
Neuroleptic Malignant Syndrome | N | N or |
Signs and Symptoms Comparison
Toxidromes Signs and Symptoms Comparison
Adapted from: Toronto Notes 2017. University of Toronto Press, 2017.Toxidrome | Overdose Signs and Symptoms | Examples |
---|---|---|
Anticholinergic | • ”Blind as a bat” (blurred vision, dilated pupils) • “Dry as a bone” (dry mouth and skin) • “Red as a beet” (vasodilation/flushing) • “Mad as a hatter” (confusion, cognitive impairment, delirium, agitation, hallucinations, tremors, ataxia) • “Hot as a hare” (hyperthermia) • “And the heart runs alone” (tachycardia) | • Antidepressants (e.g. TCAs) • Cyclobenzaprine (Flexeril®) • Carbamazepine • Antihistamines (e.g. diphenhydramine) • Antiparkinsonians • Antipsychotics • Antispasmodics • Belladonna alkaloids (e.g. atropine) |
Cholinergic | • S - Salivation• L - Lacrimation• U - Urination• D - Diaphoresis• G - GI Upset• E - Emesis• Bradycardia and pin-point pupils can result as well! | • Natural plants: mushrooms, trumpet flower • Anticholinesterases: physostigmine • Insecticides (organophosphates, carbamates) • Nerve gases |
Extrapyramidal | • Dysphonia, dysphagia • Rigidity and tremor • Motor restlessness, crawling sensation (akathisia) • Constant movements (dyskinesia) • Dystonia (muscle spasms, laryngospasm, trismus, oculogyric crisis, torticollis) | • Major tranquilizers • Antipsychotics |
Hemoglobin Derangements | • Increased respiratory rate • Decreased LOC • Seizures • Cyanosis unresponsive to O2 • Lactic acidosis | • CO poisoning (carboxyhemoglobin) • Drug ingestion (methemoglobin, sulfmethemoglobin) |
Opioid | • Hypothermia • Hypotension • Respiratory depression • Dilated or constricted pupils (pinpoint in opioid) • CNS depression | • Opioids (morphine, heroin, fentanyl, etc.) |
Sedative/ Hypnotic, Alcohol | • Drowsiness • Slurred speech • Nystagmus • Hypotension • Ataxia • Coma • Respiratory depression • Cardiorespiratory arrest | • Alcohol • Benzodiazepines • Barbiturates • Gamma hydroxybutyrate (GHB) |
Sympathomimetic | • Increased temperature • CNS excitation (including seizures) • Tachycardia, HTN • N/V • Diaphoresis • Dilated pupils | • Amphetamines, caffeine, cocaine, LSD, phencyclidine • Ephedrine and other decongestants • Thyroid hormone • Sedative or EtOH withdrawal |
Serotonin Syndrome | • Mental status changes • Dilated pupils • Autonomic hyperactivity • Hyperreflexia • Clonus • Hyperthermia • Diarrhea • HTN | MAOI, TCA, SSRI, opiate analgesics Cough medicine, weight reduction medications |
Neuroleptic Malignant Syndrome | • Diaphoresis • Hyperthermia • CK elevation • Autonomic hyperactivity (hypertension, HR/RR increase) • “Lead-pipe” rigidity • Bradyreflexia | Dopamine antagonists |