Correct Answer: A

Rationale: Visual disturbances, such as blurred or yellow vision, can be an early sign of digoxin toxicity. Monitoring for visual changes is crucial to detect and prevent potential adverse effects of digoxin.

Correct Answer: D

Rationale: When administering an antiulcer agent, caution is warranted in patients with renal failure due to the potential impact on drug metabolism and excretion. Additionally, elderly patients may be more susceptible to adverse effects from antiulcer agents due to age-related physiological changes. Therefore, it is important to be more cautious when administering antiulcer agents to patients with renal failure and elderly patients.

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: A

Rationale: Spironolactone, a potassium-sparing diuretic, can lead to hyperkalemia due to its mechanism of action. Hyperkalemia, or elevated potassium levels, can result in serious cardiac complications and requires immediate medical attention. Therefore, the nurse should promptly report any signs or symptoms of hyperkalemia to prevent potential adverse outcomes in the patient.

Correct Answer: D

Rationale: A therapeutic response to levothyroxine is indicated by a decrease in the level of TSH. This decrease signifies that the body requires less stimulation to produce thyroid hormone, reflecting a normalization of thyroid function due to the medication's effectiveness.