Activated Charcoal
Indications
Activated Charcoal is used for:
Poisonings, Drug overdose, Gastrointestinal disorders
Adult Dose
Oral
Acute oral poisoning
Adult: 25-100 g as a single dose. For multiple-dose treatment: 50-100 g as an initial dose followed by not <12.5 g every hr. Alternatively, 25 mg every 2 hr or 50 mg every 4 hr.
Minimum dose = 25 g
Commonly used with sorbitol 25 g; multiple dose regimen 25 g PO q2hr or 50 g q4hr without sorbitol
DO NOT give sorbitol after first dose due to risk for severe diarrhea; use aqueous solution
Child: <1 yr: 1 g/kg/dose may repeat q4-6hr; 1-12 yr: 25-50 g/dose may repeat q4-6hr.
Gastrointestinal disorders
Adult: 0.975 - 3.9 g tid.
Child Dose
Oral
Acute oral poisoning
Child: <1 yr: 1 g/kg/dose may repeat q4-6hr; 1-12 yr: 25-50 g/dose may repeat q4-6hr.
Renal Dose
Administration
Contra Indications
Cyanide, mineral acids, caustic alkalis, organic solvents, iron, ethanol, methanol poisoning; lithium, methionine; intestinal obstruction, anatomically-broken GI tract, haemorrhage or GI perforation. Concomitant use of charcoal with sorbitol: Patients with fructose intolerance; Childn <1 yr.
Precautions
Decreased peristalsis: administer within 1 hr of ingestion. Induce vomiting of ipecac syr before admin of charcoal to prevent adsorption of ipecac. Petroleum distillate, caustic ingestions may harm gastric lining upon induction of vomiting by charcoal. Limit admin of charcoal in sorbitol doses to prevent loss of fluid and electrolyte. Monitor for active bowel sounds before administering charcoal. Pregnancy.
Pregnancy-Lactation
Interactions
Reduces absorption of most drugs from GI tract. Decreases effectiveness of methionine via adsorption. Decreases ipecac effect.
Adverse Effects
Side effects of Activated Charcoal :
Vomiting, constipation, diarrhoea, black stools, swelling of abdomen, bowel obstruction; platelet aggregation, charcoal embolism, thrombocytopenia, haemorrhage, hypoglycaemia, hypocalcaemia, hypothermia, hypotension (haemoperfusion with activated charcoal); blackening of teeth and mouth; hypernatraemia, hypokalaemia, hypermagnesemia (with concomitant admin with cathartics).
Mechanism of Action
Charcoal due to its large surface area, inhibits the GI absorption of toxic substances or irritants eg, aromatic or benzenoid-type substances through adsorption. As a laxative, the addition of sorbitol provides hyperosmotic environment thus causing catharsis. Moreover, charcoal interferes with the enterohepatic circulation of bile acids resulting to a lower cholesterol level.