Nouns

(n)narcotica drug that produces numbness or stupor; often taken for pleasure or to reduce pain; extensive use can lead to addiction

Adjectives

(a)narcoticof or relating to or designating narcotics“narcotic addicts”, “narcotic stupor”
(s)narcotic, narcotizing, narcotisinginducing stupor or narcosis“narcotic drugs”
(s)narcotic, soporiferous, soporificinducing mental lethargy“a narcotic speech”