This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Psychiatric Illness, Subject name: Pharmacology
Which of the following adverse effect of levodopa is not blocked by carbidopa? 
Select and explain. 
A. Vomiting, B. Hypotension, C. Psychosis, D. Tachycardia
C: Psychosis
Answer: C: Psychosis 
Explanation: Levodopa - CARBIDOPA / BENSERAZIDE: Peripheral DOPA decarboxylase inhibitors. - So peripheral adverse effects will decrease - More L-DOPA will enter the brain and efficacy will increase The adverse effects are more due to deposition of DOPA in the brain. DOPA deposition leads to psychosis i.e. abnormal behaviour and dyskinesia. These effects cannot be decreased by carbidopa.