What are the side effects of activated charcoal?
Charcoal may cause constipation when taken for a drug overdose or accidental poisoning. A laxative should be taken after the crisis is over. Activated charcoal may cause the stool to turn black. This side effect is to be expected. Patients should consult a doctor if they have pain or swelling of the stomach. Source: The Gale Group. Gale Encyclopedia of Medicine, 3rd ed.