What medication should a nurse administer to a client who has taken an overdose of acetaminophen?

Acetylcysteine is the correct medication to administer in the event of an acetaminophen overdose. It acts as an antidote by replenishing glutathione stores in the liver, which helps detoxify the harmful metabolite of acetaminophen, known as N-acetyl-p-benzoquinone imine (NAPQI). When acetaminophen is taken in excess, it can overwhelm the liver's capacity to process it safely, leading to potentially severe liver damage.

Acetylcysteine works most effectively when given within 8 to 10 hours of ingestion, but it can still provide benefits even if administered later. It is typically administered via intravenous infusion or orally, depending on the clinical scenario and the severity of the overdose.

Other choices may seem relevant but do not provide the specific therapeutic effects needed for acetaminophen toxicity. Ibuprofen, for example, is an NSAID and would not mitigate the effects of acetaminophen overdose. Activated charcoal is sometimes used in overdose situations to absorb the drug if the patient presents early enough post-ingestion, but it does not counteract the toxic effects on the liver. Atropine is used to treat symptoms such as bradycardia or certain types of poisoning,