Correct Answer: C

Rationale: Methylnaltrexone is an opioid antagonist used to treat severe constipation unresponsive to laxatives in opioid-dependent clients. It functions by blocking the mu opioid receptors in the gastrointestinal tract, helping alleviate constipation associated with opioid use.

Correct Answer: D

Rationale: The nurse should monitor the client for hemorrhagic cystitis when receiving cyclophosphamide due to its potential to cause bladder irritation and lead to this serious adverse effect. It is essential to assess for symptoms such as hematuria, dysuria, and flank pain.

Correct Answer: B

Rationale: Dry mouth is a common adverse effect associated with Clonidine use. Clonidine is known to cause a reduction in saliva production, leading to dry mouth. Monitoring for this adverse effect is essential to ensure client comfort and compliance with the medication.

Correct Answer: B

Rationale: In case anginal pain persists after taking the first tablet and waiting 5 minutes, the priority step is to call emergency services (911) and then take a second sublingual tablet. Persistent pain could indicate a myocardial infarction, and immediate medical attention is crucial. If the pain continues even after the second tablet, the client can take a third tablet after an additional 5-minute wait.

Correct Answer: A

Rationale: The correct answer is Acetylcysteine. Acetylcysteine is the antidote for acetaminophen overdose. It works by replenishing glutathione, which is depleted in cases of acetaminophen overdose, thus preventing liver damage. Pegfilgrastim is a medication used to stimulate white blood cell production, misoprostol is a medication used to prevent gastric ulcers, and naltrexone is used in the management of opioid addiction and alcohol dependence, which are not indicated in the scenario described.