This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
All are the side effects of prolonged phenytoin therapy EXCEPT : 
Select and explain. 
A. Osteomalacia, B. Gynaecomastia, C. Megaloblastic anemia, D. Gum hyperplasia
B: Gynaecomastia
Answer: B: Gynaecomastia 
Explanation: None