1) Producing stupor 2) Stupefying 
narcotic; stupefying
• (n.) Anything promoting stupefaction; a narcotic. • (a.) Producing stupefaction; stupefactive.
(stoo″pә-fa´shәnt) inducing stupor. an agent that induces stupor; see also depressant.
Stu`pe·fa'cient adjective [ Latin stupefaciens , present participle of stupefacere to stupefy; stupere to be stupefied + facere to make. Confer Stupefy .] [ Written also stupifacient .] Producing stupefaction; stupefactive. -- noun 
stupefacient 1. Stupefying; producing stupor. 2. A drug or agent that produces stupor.
stupefying; producing stupor.