This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Which of the following is not a side effect of phenytoin? 
Select and explain. 
A. Hypoglycemia, B. Osteomalacia, C. Gum hyperophy, D. Lymphadenopathy
A: Hypoglycemia
Answer: A: Hypoglycemia 
Explanation: Side Effects. Headache, nausea, vomiting, constipation, dizziness, feeling of spinning, drowsiness, trouble sleeping, or nervousness may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Phenytoin may cause swelling and bleeding of the gums Ref: KD Tripathi 8th ed.