A nurse is teaching a client who has a seizure disorder and has a new prescription for phenytoin.Which of the following client statements indicates an understanding of the teaching?

Choice A rationaleDark urine is not a common side effect of phenytoin. Phenytoin primarily affects the central nervous system. Unusual urine color changes could indicate a different issue and should be reported to a healthcare provider for further evaluation.Choice B rationaleTaking an extra dose of phenytoin can lead to toxicity. Phenytoin has a narrow therapeutic index, and overdose can cause symptoms like ataxia, nystagmus, and confusion. Dosage adjustments should only be made under medical supervision to avoid complications.Choice C rationaleRegular blood level monitoring of phenytoin is essential to ensure therapeutic levels and avoid toxicity. Therapeutic range for phenytoin is 10-20 mcg/mL. This helps maintain efficacy and reduce the risk of side effects or subtherapeutic levels.Choice D rationaleTaking phenytoin with antacids can reduce its absorption, decreasing its effectiveness. Antacids can bind to phenytoin in the gastrointestinal tract, preventing proper absorption. Medications should be spaced appropriately to ensure optimal absorption.