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 agents do not act GABAA Cl- channel complex receptors? 
Select and explain. 
A. Zopiclone, B. Benzodiazepines, C. Thiopentone, D. Promethazine
D: Promethazine
Answer: D: Promethazine 
Explanation: Zopiclone (non benzodiazepine hypnotics ),benzodiazepine ,thiopentone(barbiturates) all act on GABA-Cl channel ,whereas promethazin is a antihistamine drug that acts on histaminergic receptors which causes high sedation. Ref: KD Tripathio 8th ed.