The Collaborative International Dictionary of English v.0.48:

mepacrine \mepacrine\ n.
   Quinacrine, a drug once used to treat malaria; Atabrine is
   a trademark.

   Syn: quinacrine, Atabrine.
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Atabrine \Atabrine\ n. [Trademark.]
   a drug once used to treat malaria (C23H30ClN3O); chemically
   it is a derivative of the tricyclic structure acridine:

   6-chloro-9-[[4-(diethylamino-1-methylbutyl)]amino]-2-methoxyacridine.
   It also has some anthelmintic activity against cestodes.
   Atabrine is a trademark.

   Syn: quinacrine, mepacrine.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Atabrine
    n 1: a drug (trade name Atabrine) used to treat certain worm
         infestations and once used to treat malaria [syn:
         quinacrine, quinacrine hydrochloride, mepacrine,
         Atabrine]