Toxicology is a deep complex topic area, which can devour a disproportionate amount of studying time in preparation for the boards. Unlike many other subjects however, it lends itself to some word associations and other high value studying. This list has been compiled to facilitate some rapid review.

Basic Word Associations

  • Acetaminophen – NAC
  • Anticholinergic Toxidrome (Jimsonweed, Benadryl, Atropine) – Physostigmine
  • Benzodiazepine – Flumazenil
  • Beta Blocker – Glucagon
  • Calcium-Channel Blocker – Calcium, Insulin
  • CO – High Flow O2, Hyperbaric Therapy
  • Cholinergic Toxidrome – Atropine, Pralidoxime (2-PAM)
  • Cyanide – Sodium Nitrite, Sodium Thiosulfate, Hydroxocobalamin
  • Digoxin – Fab Fragments (Digibind/Digifab)
  • Ethylene Glycol/Methanol – Ethanol, Fomepizole, Dialysis
  • Methemoglobinemia (Benzocaine, Lidocaine – Methylene Blue
  • INH – Pyridoxine (Vitamin B6)
  • Heavy Metals – Chelation
  • Opiates – Naloxone
  • ASA – Sodium Bicarbonate Alkalinization
  • Sulfonylureas (Glipizide/Glyburide) – Octreotide
  • Valproic Acid – Carnitine
  • TCAs – Sodium Bicarbonate
  • Hydrofluoric Acid – Calcium

Pharmacologic Effects of TCAs

K+ Channel Blockade QTC Prolongation
NE & Serotonin Reuptake Inhibition Initial hypertension quickly followed by hypotension
Na+ Channel Blockade QRS Prolongation
Hypotension — depresses myocardial contractility
Ventricular dysrhythmias
Brugada-like findings on EKG
Muscarinic Anticholinergic Receptor Antagonism Anticholinergic Toxidrome
Antihistaminergic CNS stimulation or sedation
alpha1 Adrenergic Antagonism Hypotension
GABA-A Receptor Blockade Seizures

Toxic Alcohols

  • Isopropanol –> Acetone = Ketosis w/o Acidosis
  • Methanol –> Formic Acid –> Optic Nerve/Retina
  • Ethylene Glycol –> Glycolic Acid –> Oxalic Acid –> Calcium Oxalate –> Kidney
  • Anion Gap = Na+ – (Cl- + HCO3-)
    • ↑AG due to unmeasured anions  organic acid metabolites.
  • Osmolar Gap = 2Na+ + (BUN/2.8) + (Glucose/18) + (EtOH/4.6)
    • ↑ OG due to unmeasured parent compound.
  • HD Indications:
    • End-Organ Toxicity
    • Severe Acidosis – after resuscitation
    • Methanol > 50

Cyanide Treatments

  • Hydroxocobalamin is new standard i