Correct Answer: A

Rationale: Allopurinol is an antigout medication that works by reducing the production of uric acid in the body. To prevent kidney stones and promote the excretion of uric acid, increased fluid intake is essential. Instructing the client to drink 3000 mL of fluid per day helps to reduce the risk of kidney stones and assists in the elimination of uric acid, thereby enhancing the effectiveness of allopurinol therapy.

Correct Answer: C

Rationale: Clients taking metformin (Glucophage) should avoid alcohol as it can increase the risk of lactic acidosis. Metformin should be taken with meals to reduce gastrointestinal upset. While hypoglycemia is less common with metformin compared to other diabetes medications, clients should still be aware of its symptoms.

Correct Answer: B

Rationale: The correct answer is to increase fluid intake to 2000 to 3000 mL daily. Cyclophosphamide can cause hemorrhagic cystitis as a toxic effect. By increasing fluid intake, the client can help prevent this complication by promoting frequent urination, which reduces the concentration of the drug and its metabolites in the bladder. This dilution effect can help reduce the risk of bladder toxicity.

Correct Answer: A

Rationale: The correct answer is A. Cyclosporine is an immunosuppressant that can reduce the effectiveness of vaccines. Clients should avoid vaccinations without consulting their health care provider to prevent potential complications or reduced efficacy of the vaccines.

Correct Answer: B

Rationale: Before administering Isotretinoin, it is important to check the client's triglyceride levels. Isotretinoin is known to elevate triglyceride levels, hence monitoring them before and periodically during treatment is essential to prevent potential adverse effects.