Overdose & Poisoning

• Every poisoning gets ABCs + glucose + ECG (QRS/QT); call the poison center early.
• Key antidotes to remember: naloxone (opioids), NAC (paracetamol), fomepizole (toxic alcohols), NaHCO₃ (TCA; target pH 7.50–7.55), Fab (digoxin), atropine+pralidoxime (OP), lipid emulsion (local anesthetics).
• Alkalinize urine for salicylates (pH 7.5–8.5); dialyze if altered mental state or renal failure.
• Reserve gastric lavage/whole-bowel irrigation for select lethal ingestions; single-dose charcoal only within 1 h when the airway is protected.
• Salicylate poisoning declares itself as tinnitus with a mixed respiratory alkalosis and high-anion-gap acidosis: alkalinise the urine, replace potassium before alkalinisation can work, refer early for dialysis, and avoid intubation — losing the patient's own hyperventilation collapses the pH and drives salicylate into the brain.

Undifferentiated overdose / poisoning

First tests: Blood glucose, 12-lead ECG, Sodium, potassium, bicarbonate, urea and creatinine, Venous blood gas.

Only if indicated: Paracetamol/acetaminophen concentration, Salicylate concentration, Measured serum osmolality, Pregnancy test, Targeted drug/toxin tests.

Repeat monitoring: 12-lead ECG.

Paracetamol / acetaminophen poisoning

First tests: Paracetamol/acetaminophen concentration, Liver biochemistry, PT/INR, Sodium, potassium, bicarbonate, urea and creatinine.

Only if indicated: Blood glucose, Blood lactate.

Repeat monitoring: Paracetamol/acetaminophen concentration.

Organophosphate / carbamate poisoning

First tests: Clinical toxidrome and respiratory assessment, Blood glucose, 12-lead ECG, Sodium, potassium, bicarbonate, urea and creatinine.

Only if indicated: Plasma / red-cell cholinesterase, Arterial blood gas, Chest X-ray.

Repeat monitoring: Respiratory strength and gas exchange.

Opioid overdose

First tests: Respiratory rate, ventilation and consciousness, Blood glucose, 12-lead ECG.

Only if indicated: Arterial blood gas, Chest X-ray, Targeted co-ingestant tests, Creatine kinase.

Repeat monitoring: Ventilation and consciousness monitoring.

Salicylate poisoning

First tests: Serum salicylate concentration, Arterial blood gas, Sodium, potassium, bicarbonate, urea and creatinine, Blood glucose.

Only if indicated: Chest X-ray, Urine pH.

Repeat monitoring: Salicylate concentration, Sodium, potassium, bicarbonate, urea and creatinine.

• Key Initial Steps in Managing the Poisoned Patient
• Organophosphate and Carbamate Poisoning
• Paracetamol (Acetaminophen) Overdose
• Opioid Overdose and Naloxone Titration
• Salicylate (Aspirin) Poisoning