What is the purpose of administering activated charcoal in cases of aspirin overdose?

Activated charcoal is administered in cases of aspirin overdose primarily to adsorb the aspirin in the gastrointestinal tract, thereby reducing its systemic absorption. Activated charcoal has a large surface area that allows it to bind many types of drugs, including aspirin, effectively preventing them from entering the bloodstream.

While aspirin is an acidic drug, the administration of activated charcoal itself does not alter urine pH but focuses on minimizing the absorption of the toxic agent. The idea behind making urine basic is associated with the elimination of acidic drugs, as ionized forms of drugs are less likely to be reabsorbed in the renal tubules. However, the immediate role of activated charcoal is to reduce absorption in the gut, which is why it is the appropriate choice in this scenario.

Other options, such as neutralizing stomach acid or promoting vomiting, do not address the primary mechanism by which activated charcoal functions as an antidote. Similarly, increasing gastric motility is not relevant to the efficacy of activated charcoal in managing an aspirin overdose. Thus, the rationale behind administering activated charcoal hinges primarily on its ability to adsorb the aspirin, reducing its effect and preventing further systemic toxicity.