Pharmacology · patient case question
Which oral side effect is associated with long-term valproic acid therapy?
Patient case: Autistic patient taking an antiepileptic
Patient: Patient with autism spectrum disorder
Chief complaint: Attends for routine dental care.
Background: Epilepsy, treated with valproic acid. History of generalised tonic–clonic seizures.
Current findings: Cooperative with a structured, predictable approach.
Show answer and explanation
Correct answer: A. Increased bleeding tendency from thrombocytopenia and platelet dysfunction
- A. CORRECT. Valproate causes dose-dependent THROMBOCYTOPENIA and impairs platelet function, so bleeding after surgical procedures is the relevant concern. A platelet count and coagulation screen are worth obtaining before surgery. Valproate is also hepatotoxic, which matters for drug selection.
- B. Gingival overgrowth is classically associated with PHENYTOIN, and also with ciclosporin and calcium channel blockers such as nifedipine — not valproate.
- C. Intrinsic staining is associated with tetracycline exposure during development.
- D. Valproate does not characteristically cause xerostomia.
Note: Distinguish carefully: PHENYTOIN causes gingival overgrowth; VALPROATE causes bleeding tendency.