A nurse is instructing a client regarding Carbidopa-levodopa (Sinemet) for the treatment of Parkinson's Disease. The nurse tells the client which of the following is a side effect of the medication?

Choice A rationale: Prednisone can potentiate the effects of beta-blockers like metoprolol, and dose adjustments may be necessary to avoid excessive bradycardia.
Choice B rationale: Acetaminophen is not typically affected by prednisone in a way that requires dose adjustment.
Choice C rationale: Lisinopril is not typically affected by prednisone in a way that requires dose adjustment.
Choice D rationale: Insulin may need adjustment due to the hyperglycemic effects of prednisone.

Choice A rationale: Allopurinol dosing is not typically adjusted based on target serum drug levels.
Choice B rationale: The absence of gastrointestinal (GI) effects is not a parameter used to adjust the dosing of allopurinol.
Choice C rationale: This is partially correct. Allopurinol dosing is adjusted based on renal function, but specifically, it is adjusted based on serum creatinine levels. The higher the creatinine levels, the lower the dose of allopurinol should be.
Choice D rationale: This is correct. Allopurinol dosing is adjusted based on plasma urate levels. The goal is to reduce uric acid levels in the blood to prevent the formation of urate crystals and subsequent gout attacks. Regular monitoring of plasma urate levels helps determine the effectiveness of the medication, and adjustments can be made to achieve the target urate level.