A nurse is reinforcing teaching about phenytoin with a client who had a tonic-clonic seizure. Which of the following information should the nurse include in the teaching?

B. Phenytoin is associated with gingival hyperplasia, which is an overgrowth of gum tissue. It's essential for clients taking phenytoin to maintain good oral hygiene and receive regular dental check-ups to monitor for this side effect. A. Phenytoin is not known to directly diminish potassium levels. However, it can cause a variety of electrolyte imbalances, including hyponatremia (low sodium levels) and hypocalcemia (low calcium levels), but not typically hypokalemia (low potassium levels). C. Ginkgo biloba is an herbal supplement that does not interact with phenytoin. D. Phenytoin can cause photosensitivity reactions in some individuals, leading to an increased risk of sunburn. However, teaching on gingival hyperplasia is more important.