Which adverse effect should a client receive education about when taking phenytoin?

A. Gingival hyperplasia: Phenytoin can cause overgrowth of gum tissue, particularly in children and young adults, due to its effects on fibroblast proliferation. Clients should be educated on proper oral hygiene, regular dental visits, and early reporting of gum changes to prevent complications. B. Weight loss: Phenytoin is not typically associated with weight loss. Appetite changes or metabolic effects are uncommon, making this an unlikely adverse effect of clinical concern. C. Hypertensive episodes: Phenytoin does not usually elevate blood pressure. Cardiovascular effects are rare and generally limited to hypotension during rapid IV administration, not hypertension. D. Hair loss: Alopecia is not a common adverse effect of phenytoin therapy. Hair loss may occasionally occur with other medications but is not characteristic of this anticonvulsant.