The antitussive activity of levodropropizine S(-)3-(4-phenyl-piperazin
e-1-yl)-propane-1,2-diol, DF 526, CAS 99291-25-5) was evaluated after
oral administration to the conscious dog. Levodropropizine had a good
antitussive activity, comparable with, but having a longer duration of
action than dropropizine, the racemate front which it is derived The
antitussive activity of levodropropizine in the dog was approximately
1/20 of that of codeine phosphate.