The Collaborative International Dictionary of English v.0.48:

Narcotize \Nar"co*tize\ (n[aum]r"k[-o]*t[imac]z), v. t. [imp. &
   p. p. Narcotized (n[aum]r"k[-o]*t[imac]zd); p. pr. & vb. n.
   Narcotizing (n[aum]r"k[-o]*t[imac]*z[i^]ng).]
   To imbue with, or subject to the influence of, a narcotic; to
   put into a state of narcosis.
   [1913 Webster]

WordNet (r) 3.0 (2006):

narcotize
    v 1: administer narcotics to [syn: narcotize, narcotise]

Moby Thesaurus II by Grady Ward, 1.0:

37 Moby Thesaurus words for "narcotize":
   KO, anesthetize, bedaze, benumb, besot, blunt, chloroform,
   coldcock, deaden, desensitize, dope, drug, dull, entrance,
   etherize, freeze, hypnotize, kayo, knock out, knock senseless,
   knock stiff, knock unconscious, lay out, lull to sleep, magnetize,
   mesmerize, numb, obtund, palsy, paralyze, put to sleep, put under,
   rock to sleep, sedate, stun, stupefy, trance