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
All are true regarding METHANOL poisoning except: 
Select and explain. 
A. Hemodialysis should be done when serum methanol cencentration is above 50 mg/dl, B. Fomepizole acts by inhibiting aldehyde dehydrogenase, C. High anion gap metabolic acidosis is seen in severe cases, D. Visual disturbances are commonly seen
B: Fomepizole acts by inhibiting aldehyde dehydrogenase
Answer: B: Fomepizole acts by inhibiting aldehyde dehydrogenase 
Explanation: Ref: Katzung 12/e p398 Fomepizole inhibits alcohol dehydrogenase and not aldehyde dehydrogenase *Serum methanol concentration above 20 mg/dl is an indication to sta treatment and above 50 mg/dl is for Hemodialysis. *Metabolic product formaldehyde and fornic acid is responsible for blindness and high anion gap metabolic acidosis.