What is a common side effect of long-term phenytoin use that the nurse should educate the client about?

Phenytoin is an antiepileptic medication commonly used to manage seizure disorders. One of the notable side effects associated with long-term use of phenytoin is gingival hyperplasia, which is the overgrowth of gum tissue. This condition occurs due to the drug's effects on fibroblast growth and inflammatory responses in periodontal tissues.

Nurses should educate clients about this potential side effect because good oral hygiene becomes increasingly important to manage and prevent the condition. Patients may need to be encouraged to maintain regular dental check-ups and to be vigilant about their oral care routines, as the gum overgrowth can lead to difficulties with eating and oral hygiene, potentially resulting in further complications if left untreated.

Other options, such as constipation, weight loss, and vision improvement, are not recognized as common side effects of phenytoin. While individual responses to medications can vary, these particular effects are not typically associated with the long-term use of this drug.