Neuro-pharmacology · USMLE Step 1

A patient taking phenytoin presents with gingival hyperplasia. What mechanism explains this adverse effect?

  1. Reduced bone density
  2. Increased fibroblast growth
  3. Direct mucosal irritation
  4. Immune-mediated inflammation
Show answer and explanation

Correct answer: Increased fibroblast growth

Phenytoin stimulates fibroblast growth and collagen deposition, causing gingival enlargement.

Difficulty: Medium Question 8 of 20

Practice all 20 Neuro-pharmacology questions

Keep practicing

More Neuro-pharmacology questions