Questions: A provider counsels a patient who is prescribed phenytoin for epilepsy. Which statement by the patient indicates understanding of the teaching? "I can consume alcohol in moderation while taking this drug." "Rashes are a common side effect but are not serious." "I should brush and floss my teeth regularly." "Once therapeutic blood levels are reached, they are easy to maintain."

The answer is the third one: "I should brush and floss my teeth regularly."

Explanation for each option:

1. "I can consume alcohol in moderation while taking this drug." - This statement is incorrect. Alcohol can interact with phenytoin, potentially affecting its metabolism and leading to either increased side effects or decreased effectiveness. Patients are generally advised to avoid alcohol or discuss its use with their healthcare provider.

2. "Rashes are a common side effect but are not serious." - This statement is incorrect. While rashes can occur with phenytoin, they can sometimes indicate a serious condition such as Stevens-Johnson syndrome or toxic epidermal necrolysis. Any rash should be reported to a healthcare provider immediately.

3. "I should brush and floss my teeth regularly." - This statement is correct. Phenytoin can cause gingival hyperplasia (overgrowth of the gums), so maintaining good oral hygiene is important to minimize this side effect.

4. "Once therapeutic blood levels are reached, they are easy to maintain." - This statement is incorrect. Phenytoin has a narrow therapeutic range and its metabolism can be affected by various factors, making it challenging to maintain stable blood levels. Regular monitoring is often required.

In summary, the correct statement indicating understanding of the teaching is about maintaining good oral hygiene to prevent gum overgrowth associated with phenytoin use.