Which of the following medications is indicated for acetaminophen overdose?

Acetylcysteine is the treatment of choice for acetaminophen overdose because it acts as a hepatoprotective agent by replenishing intracellular glutathione levels. When acetaminophen is taken in excessive amounts, it can overwhelm the liver's ability to safely metabolize and eliminate it, leading to the production of toxic metabolites that can cause severe liver damage. Acetylcysteine works by binding to these harmful metabolites, thus preventing cellular damage and preserving liver function.

Gastric lavage and activated charcoal may be used in specific contexts for poisonings or overdoses, particularly for substances that can be removed from the gastrointestinal tract, but they are not the primary treatment for acetaminophen overdose. The effectiveness of these interventions diminishes significantly after a certain time has passed since ingestion. Acetaminophen itself would not be helpful in an overdose situation, as it would only exacerbate the problem. Therefore, acetylcysteine stands out as a targeted antidote that is specifically formulated to address the toxicity associated with acetaminophen overdose.