This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: JIPMER 2017, Subject name: Pharmacology
All can cause serotonin increase except: 
Select and explain. 
A. MDMA, B. Amphetamine, C. Fluoxetine, D. LSD
D: LSD
Answer: D: LSD 
Explanation: Stimulant drugs commonly abused in the USA include methamphetamine (crank, crystal) methylenedioxymethamphetamine (MDMA, ecstasy) act's to increase 5HT. SSRI like fluoxetine and paroxetine increase serotonin level and can lead to excessive serotonin response when administered with other serotonergic drug like MAOIs. LSD act on 5HT serotonin receptor but does not increase serotonin level.