Correct Answer: B

Rationale: Naloxone is the drug of choice for managing opioid overdoses as it competitively antagonizes opioid receptors, reversing the respiratory depression and sedation caused by opioids. It is essential in the emergency treatment of opioid overdose to prevent fatal outcomes.

Correct Answer: C

Rationale: Ondansetron can cause tremors as an adverse effect. Monitoring for tremors is essential as it can indicate a potential adverse reaction to the medication and prompt intervention is necessary to ensure the client's safety and comfort.

Correct Answer: B

Rationale: Phenytoin is primarily used as an anticonvulsant to prevent and control seizures. It works by stabilizing electrical activity in the brain, making it effective in managing conditions like epilepsy. Antidiabetic medications are used to regulate blood sugar levels, mood stabilizers help manage mood disorders, and antianxiety agents are used to reduce anxiety symptoms, none of which are the primary therapeutic action of Phenytoin.

Correct Answer: D

Rationale: Maraviroc, used to treat HIV infection, can lead to severe allergic reactions, including hepatotoxicity. Monitoring for signs of liver damage, such as jaundice or right upper quadrant pain, is crucial for early detection and intervention.

Correct Answer: C

Rationale: Liver failure impairs metabolism, leading to increased medication concentrations. To prevent adverse effects, lower dosages are required when liver function is compromised.