Decontamination and Enhanced Elimination
Decontamination — reducing absorption of ingested toxins — and enhanced elimination — increasing the rate of toxin removal — are adjuncts to specific antidote therapy that may be useful in selected cases.
| Method | Indication | Contraindications and Cautions |
| Activated charcoal (50g PO) | Effective for many drugs if given within 1 hour of ingestion | Contraindicated in: reduced consciousness without airway protection; caustic ingestion; hydrocarbons. Less effective for: iron, lithium, alcohol, cyanide |
| Gastric lavage | Rarely used now; may benefit within 1 hour of life-threatening ingestion | Requires airway protection if drowsy; risk of aspiration; not recommended routinely |
| Whole bowel irrigation (polyethylene glycol) | Modified-release preparations; iron; lithium; body packers | Contraindicated in: bowel obstruction, perforation, haemodynamic instability |
| Urinary alkalinisation (sodium bicarbonate) | Salicylate (aspirin) overdose — increases ionised form in urine, trapping it | Requires monitoring of urinary pH (target 7.5–8.5) and serum electrolytes |
| Haemodialysis / haemodiafiltration | Lithium, salicylates, metformin, toxic alcohols (methanol, ethylene glycol) | Requires ICU; drug must be dialysable (small, water-soluble, low protein binding) |
| Lipid emulsion therapy | Local anaesthetic toxicity (bupivacaine); some lipophilic drug toxicities | Specialist use; mechanism of action not fully established |