Correct Answer: A

Rationale: The correct answer is to check the thyroid hormone assay. Long-term lithium use can result in thyroid dysfunction, making it crucial to monitor the client's thyroid function regularly to detect any abnormalities early and prevent potential complications. Liver function tests (choice B) are not specifically associated with lithium therapy. Erythrocyte sedimentation rate (choice C) is a nonspecific test for inflammation and not directly related to lithium therapy. Brain natriuretic peptide (choice D) is a test used to diagnose heart failure and is not relevant to monitoring lithium therapy.

Correct Answer: B

Rationale: The correct answer is B. Visual changes, such as yellow or blurred vision, can be indicative of digoxin toxicity. It is crucial for clients to inform their healthcare provider promptly if they encounter these symptoms. Prompt medical attention can help manage potential toxicity and prevent complications. Choices A, C, and D are incorrect because taking an extra dose of Digoxin, stopping Digoxin based on heart rate alone, and using antacids for gastrointestinal upset are not appropriate actions when managing Digoxin toxicity.

Correct Answer: D

Rationale: The correct instruction for a client prescribed with Cephalexin is to complete the full course of medication. This is crucial to ensure the infection is completely treated and to reduce the risk of antibiotic resistance. Choices A, B, and C are incorrect. Taking Cephalexin with an antacid is generally not recommended as it may reduce its effectiveness. While dairy products can interfere with certain antibiotics, they do not have a direct interaction with Cephalexin. Stools turning black is not an expected side effect of Cephalexin.

Correct Answer: C

Rationale: An elevated BUN level of 55 mg/dL should be reported before starting amphotericin B due to its nephrotoxic effects. Amphotericin B can cause kidney damage, and an elevated BUN indicates impaired kidney function, increasing the risk of further renal damage with this medication. Sodium, potassium, and glucose levels are not directly associated with the nephrotoxic effects of amphotericin B, making choices A, B, and D incorrect.

Correct Answer: D

Rationale: Metformin is excreted by the kidneys, and impaired kidney function can lead to an increased risk of lactic acidosis, a serious side effect. Therefore, it is important to monitor kidney function regularly while a client is on Metformin. Hemoglobin A1C is used to monitor long-term glucose control, but kidney function is the priority for monitoring Metformin therapy.