sobering

from WordNet (r) 3.0 (2006)

sobering
    adj 1: tending to make sober or more serious; "the news had a
           sobering effect"

from The Collaborative International Dictionary of English v.0.48

Sober \So"ber\, v. t. [imp. & p. p. {Sobered}; p. pr. & vb. n.
   {Sobering}.]
   To make sober.
   [1913 Webster]

         There shallow draughts intoxicate the brain,
         And drinking largely sobers us again.    --Pope.
   [1913 Webster]