When is activated charcoal indicated in poisoning and what are contraindications?

When is activated charcoal indicated in poisoning and what are contraindications?

• A. Within 1-2 hours of ingestion; not for caustics, hydrocarbons, heavy metals; risk of aspiration; ensure airway protection if indicated.
• B. Within 4-6 hours of ingestion; not for any caustics.
• C. Indicated for all poisons regardless of time; no airway concerns.
• D. Never indicated in poisoning management.

Answer: (A)

Activated charcoal works by binding many toxins in the gastrointestinal tract to prevent absorption, so its benefit is greatest when given promptly after ingestion. The key window is about one to two hours; beyond that, its effectiveness decreases. It should not be used for caustic substances or hydrocarbons because they can cause further injury or are not reliably adsorbed, and it’s not effective for certain toxins like heavy metals (for example iron, lithium) that require other treatments. Because charcoal carries a real risk of aspiration, airway protection is essential if the patient cannot reliably protect their airway or is vomiting or obtunded. In short, use activated charcoal within 1–2 hours for toxins that are adsorbable, only after securing an airway if needed, and avoid it for caustics, hydrocarbons, heavy metals, or when airway protection isn’t possible.

Activated charcoal works by binding many toxins in the gastrointestinal tract to prevent absorption, so its benefit is greatest when given promptly after ingestion. The key window is about one to two hours; beyond that, its effectiveness decreases. It should not be used for caustic substances or hydrocarbons because they can cause further injury or are not reliably adsorbed, and it’s not effective for certain toxins like heavy metals (for example iron, lithium) that require other treatments. Because charcoal carries a real risk of aspiration, airway protection is essential if the patient cannot reliably protect their airway or is vomiting or obtunded. In short, use activated charcoal within 1–2 hours for toxins that are adsorbable, only after securing an airway if needed, and avoid it for caustics, hydrocarbons, heavy metals, or when airway protection isn’t possible.