Drug Causing Sleep or Drowsiness

Puzzle 7 of Emergency Workers Easy Pack

Question is: Drug Causing Sleep or Drowsiness

and the answer is: NARCOTIC

Word Meaning:

NARCOTIC — (pharmacology) Any substance or drug that reduces pain, induces sleep and may alter mood or behaviour; in some contexts, especially in reference to the opiates-and-opioids class, especially in reference to illegal drugs, and often both.

Definitions from Wiktionary.