Differences Between Gastric Lavage and Activated Charcoal in Treating Poisoning
Gastric lavage and activated charcoal are fundamentally different decontamination methods for poisoning, with gastric lavage being a mechanical removal technique while activated charcoal works through adsorption of toxins, and neither should be routinely used in first aid settings without professional medical guidance. 1
Gastric Lavage
- Gastric lavage is a mechanical method of poison removal that involves inserting a tube through the mouth into the stomach and washing out stomach contents with fluid 2
- It is no longer recommended as a routine intervention for poisoning cases and has largely been replaced by activated charcoal in emergency department settings 2
- Gastric lavage may be considered only in cases with life-threatening potential and when performed very early after ingestion (typically within 1 hour) 2
- Potential complications include aspiration pneumonia, laryngospasm, esophageal perforation, and fluid/electrolyte imbalances 2
- Studies show that combination therapy of gastric lavage followed by activated charcoal does not provide significant additional benefit compared to activated charcoal alone 3
Activated Charcoal
- Activated charcoal is an adsorbent that binds to many toxins in the gastrointestinal tract, preventing their absorption into the bloodstream 4
- It works through a physical process where toxins adhere to its large surface area, preventing systemic absorption 5
- Activated charcoal should not be administered routinely in poisoning cases but may be considered when a patient has an intact airway and presents soon after ingestion of a toxic substance 1
- The American Heart Association and American Red Cross guidelines state there is insufficient evidence to recommend for or against activated charcoal in first aid settings 1
- When indicated, the proper dosage is typically 0.5-1 g/kg body weight in children or 50 g in adults 4
- For maximum effectiveness, activated charcoal should be administered within 1 hour of poison ingestion; its efficacy decreases significantly when given later 3
Key Limitations and Contraindications
- Neither gastric lavage nor activated charcoal should be administered by lay rescuers without direction from poison control centers or emergency medical personnel 1
- Activated charcoal is ineffective for certain poisons including alcohols, cyanide, iron, lithium, and other metals 6
- Activated charcoal is contraindicated in patients with impaired consciousness and unprotected airways due to aspiration risk 4
- Both methods are contraindicated for caustic substance ingestions (strong acids or bases) as they may cause additional harm 1
- Multiple-dose activated charcoal may be beneficial for certain substances with enterohepatic circulation but should only be administered under medical supervision 1, 6
Clinical Decision Making
- Always contact poison control centers (800-222-1222 in the US) for guidance before attempting any decontamination method 1
- The decision to use either method should be based on:
- Studies show that activated charcoal administered 1 hour after ingestion can reduce drug absorption by approximately 66%, while administration at 2 hours reduces absorption by only about 23% 3
Current Recommendations
- Modern toxicology practice has moved away from routine gastric emptying procedures toward selective use of activated charcoal 2, 5
- Neither intervention should be used routinely in poisoning cases without specific indications 1
- When indicated, activated charcoal alone is generally preferred over gastric lavage for most poisonings when administered early 3
- The American Heart Association and American Red Cross state that ipecac syrup should not be used by the lay public for poisoning treatment 1
- Always prioritize airway protection and hemodynamic stabilization before considering any gastrointestinal decontamination method 1