Basics
Description
- A toxidrome is the constellation of signs and symptoms that result from the effects of a particular toxin (toxic syndrome)
- Mechanism of action varies with each class of toxin to which the patient may be exposed and the target receptors.
Diagnosis
Signs and Symptoms
Toxidromes ‚
- There are multiple toxidromes:
- Anticholinergic
- Cholinergic
- Sympathomimetic
- Hallucinogenic
- Opiate
- Sedative " “hypnotic
- Withdrawal syndromes
- Serotonin syndrome
- Malignant neuroleptic syndrome
- Anticholinergic: Mnemonic: "Blind as a bat, mad as a hatter, red as a beet, hot as a hare, dry as a bone, the bowel and bladder lose their tone, and the heart runs alone " ¯:
- Hyperthermia ( "hot as a hare)
- Dry, flushed skin ( "dry as a bone " ¯ and "red as a beet " ¯)
- Dilated pupils ( "blind as a bat " ¯)
- Delirium ( "mad as a hatter " ¯)
- Tachycardia ( "the heart runs alone " ¯)
- Hypertension
- Hyperthermia
- Urgency retention ( "bowel and bladder lose their tone " ¯)
- Decreased bowel sounds ( "bowel and bladder lose their tone " ¯)
- Seizures
- Mental status changes
- Somnolence
- Cholinergic: Mnemonic: DUMBELS for the muscarinic component:
- Muscarinic signs:
- Diarrhea, diaphoresis
- Urination
- Miosis
- Bradycardia, bronchorrhea, bronchospasm (the killer Bs)
- Emesis
- Lacrimation
- Salivation
- Nicotinic signs:
- Mydriasis
- Tachycardia
- Weakness
- Hypertension
- Fasciculations
- Sympathomimetic: Similar to anticholinergic presentation except for skin and bowel differences (diaphoresis and increased bowel sounds may be present in sympathomimetic presentations):
- Diaphoresis
- Mydriasis
- Tachycardia
- Hypertension
- Hyperthermia
- Seizures
- Increased peristalsis
- Hallucinogenic: May have significant overlap with sympathomimetic toxidrome as many sympathomimetic drugs have hallucinogenic properties (e.g., MDMA/ecstasy, cathinones, hallucinogenic amines). Other hallucinogens include LSD, psilocybin, peyote, mescaline:
- Disorientation
- Hallucinations
- Anxiety
- Panic
- Seizures
- Opiate:
- Classic triad:
- Miosis
- Hypoventilation
- Coma
- May also present with:
- Bradycardia
- Hypotension
- Hypothermia
- Decreased bowel sounds
- Sedative " “hypnotics and alcohol:
- Sedation
- Mental status changes (confusion, delirium, hallucinations)
- Vision changes (blurred vision, diplopia)
- Slurred speech
- Ataxia
- Nystagmus
- Withdrawal (alcohol, benzodiazepine, barbiturates):
- Mydriasis
- Tachycardia
- Hypertension
- Hyperthermia
- Increased respiratory rate
- Diaphoresis
- Increased bowel sounds
- Tremor
- Agitation
- Anxiety
- Hallucinations
- Confusion
- Seizures
- Withdrawal (opioid):
- Nausea
- Vomiting
- Diarrhea
- Abdominal cramps
- Increased bowel sounds
- Mydriasis
- Piloerection
- Tachycardia
- Lacrimation
- Salivation
- Hypertension
- Yawning
- Neuroleptic malignant syndrome:
- Recent treatment with typical and atypical antipsychotic medications:
- Generally occurs from hours to several weeks of starting or increasing the dose of a medication, but can occur at any time.
- Hyperthermia
- Muscular rigidity
- Diaphoresis
- Mental status changes
- Hypertension or hypotension may be seen
- Sialorrhea
- Tremor
- Incontinence
- Increased creatinine phosphokinase
- Leukocytosis
- Metabolic acidosis
- Serotonin syndrome:
- Occurs soon after the increase in dose or addition of serotonergic medications.
- Syndrome with variable presentation
- Following are most common, seen 25 " “57% of the time:
- Mental status changes (confusion, agitation, hypomania, lethargy)
- Seizures
- Myoclonus
- Hyperreflexia
- Muscle rigidity
- Tremor
- Nystagmus
- Hyperthermia
- Diaphoresis
- Tachycardia
- Hypertension
- Mydriasis
Physical Exam
- Bradycardia:
- α2-adrenergic agonists (e.g., clonidine)
- ˇ ²-blockers
- Calcium-channel blockers
- Digoxin and related substances
- Cholinergics
- Opioids
- Tachycardia:
- Sympathomimetics
- Anticholinergics
- Methylxanthines
- Tricyclic antidepressant
- Withdrawal
- Phenothiazines
- Atypical antipsychotics
- α1-blockade with reflex tachycardia
- Phosphodiesterase type 5 inhibitor (e.g., Sildenafil)
- Hyperthermia:
- Anticholinergics
- Sympathomimetics
- Serotonin syndrome
- Neuroleptic malignant syndrome
- Malignant hyperthermia
- Dinitrophenol
- Salicylates
- Withdrawal
- Hypothermia:
- Carbon monoxide
- Oral hypoglycemics
- Opiates
- Ethanol
- Sedative " “hypnotics
- α2-adrenergic agonists
- Hypertension:
- Sympathomimetics
- Anticholinergics
- Nicotine
- Phencyclidine (PCP)
- Ergot alkaloids
- Hypotension:
- α2-agonists
- α1-antagonists
- ˇ ²-blockers
- Calcium-channel blockers
- Angiotensin converting " “enzyme inhibitors
- Methylxanthines
- Nitrates
- Opioids
- Phenothiazines
- Phosphodiesterase type 5 inhibitors
- Sedative " “hypnotics
- Ethanol
- Tricyclic antidepressants
- Atypical antipsychotic medications
- Miosis:
- Cholinergics
- Clonidine
- Reserpine
- Phenothiozines
- Atypical antipsychotics
- Mydriasis:
- Anticholinergics
- Sympathomimetics
- Withdrawal (esp. opioids)
- Botulism
- Seizures:Mnemonic with a limited list of causes for toxic seizures OTIS CAMPBELL:
- Organophosphates
- Tricyclic antidepressants
- Isoniazid, insulin
- Sympathomimetics, salicylates
- Camphor, cocaine, citalopram
- Amphetamines, anticholinergic agents
- Methylxanthines (theophylline, caffeine), mushrooms (Gyromitra: monomethyl hydrazine group), meperidine
- PCP, propoxyphene, plants (nicotine, water hemlock)
- Benzodiazepine withdrawal, bupropion
- Ethanol withdrawal
- Lithium, lidocaine
- Lead, lindane
- Diaphoresis:
- Sympathomimetics
- Cholinergics
- Salicylates
- Withdrawal
- Serotonin syndrome
- Bradypnea:
- Opiates
- Sedative " “hypnotics
- Ethanol
- ˇ ³-hydroxybutyric acid and congeners
- Botulism
- Muscular receptor blockade
- Tachypnea:
- Paraquat (and other drugs that cause pneumonitis)
- Salicylates
- Sympathomimetics
- Dinitrophenol
- Methylxanthines
- Drugs that cause acidosis
Dermatologic ‚
- Mees lines:
- Arsenic
- Thallium
- Chemotherapy agents
- Radiation
- Bullae:
- Barbiturates
- Carbon monoxide
- Captopril
- Flushed or red appearance:
- Anticholinergics
- Disulfiram reactions
- Niacin
- Boric acid
- Scombroid poisoning
- Monosodium glutamate
- Carbon monoxide (frequently postmortem)
- Cyanide (rare)
- Vancomycin
- Blue skin:
- Ergotamines
- Methemoglobinemia from:
- Nitrite
- Nitrate
- Dapsone
- Aniline dye
- Phenazopyridine
- Benzocaine
- Chloroquine
- Pseudocyanosis from:
- Chlorpromazine
- Amiodarone
- Minocycline
- Silver (argyria)
- Gold (chrysiasis)
Essential Workup
Depends on ingested substance: ‚
- CBC
- Electrolytes, BUN, creatinine, glucose
- Urinalysis
- Arterial blood gas, venous blood gas
- Carboxyhemoglobin, methemoglobin levels
- Toxicology screen
- Aspirin and Acetaminophen level
- Prothrombin time
- Liver function tests
Diagnosis Tests & Interpretation
- Anion gap acidosis: Mnemonic: A CAT MUD PILES (encompasses a limited number of common causes):
- Alcohol ketoacidosis
- CO/cyanide
- Acetaminophen in fulminant hepatic failure
- Toluene
- Methanol
- Uremia
- Diabetic ketoacidosis
- Paraldehyde, phenformin/metformin
- Iron, isoniazid
- Lactic acidosis
- Ethylene glycol
- Salicylates, sodium azide, hydrogen sulfide
- Increased osmolar gap:
- Methanol
- Ethylene glycol
- Isopropyl alcohol
- Ethanol
- Acetone
- Glycerol
- Mannitol
- Glycine
Treatment
Initial Stabilization/Therapy
ABCs ‚
Ed Treatment/Procedures
Depends on ingested substance (see Poisoning; Poisoning, Gastric Decontamination) ‚
Pearls and Pitfalls
- Obtain appropriate lab tests.
- Recognize signs and symptoms and lab clues to the toxidromes.
Additional Reading
- Boyer ‚ EW, Shannon ‚ M. The serotonin syndrome. N Engl J Med. 2005;352:1112 " “1120.
- Nelson ‚ L, Lewin ‚ N, Howland ‚ MA, et al. Goldfranks Toxicologic Emergencies. 9th ed. New York, NY: McGraw-Hill; 2010.
- Weatherald ‚ J, Marrie ‚ TJ. Pseudocyanosis: Drug-induced skin hyperpigmentation can mimic cyanosis. Am J Med. 2008;121(5):385 " “386.
See Also (Topic, Algorithm, Electronic Media Element)
- Poisoning
- Poisoning, Gastric Decontamination
Codes
ICD9
- 971.0 Poisoning by parasympathomimetics (cholinergics)
- 971.1 Poisoning by parasympatholytics (anticholinergics and antimuscarinics) and spasmolytics
- 971.2 Poisoning by sympathomimetics [adrenergics]
- 969.6 Poisoning by psychodysleptics (hallucinogens)
- 965.00 Poisoning by opium (alkaloids), unspecified
ICD10
- T44.1X1A Poisoning by oth parasympath, accidental, init
- T44.3X1A Poisoning by oth parasympath and spasmolytics, acc, init
- T44.901A Poisn by unsp drugs aff the autonm nervous sys, acc, init
- T40.901A Poisoning by unsp psychodyslept, accidental, init
- T40.601A Poisoning by unsp narcotics, accidental, init
SNOMED
- 216593002 Accidental poisoning by anticholinergics (disorder)
- 61356009 Poisoning by parasympathomimetic drug (disorder)
- 45536007 poisoning by sympathomimetic drug (disorder)
- 85975005 Poisoning by psychodysleptic (disorder)
- 11196001 Poisoning by opiate AND/OR related narcotic (disorder)