Effective evaluation of treatment formats is complicated by several factors. So adequate experimental design to test drug efficacy is nearly important for establishment of therapeutic plan to analyze the effect of medical treatment according to the symptoms of dizzy patient systematically. So we have performed this study in order to evaluate the effects of various drugs on the recovery from vertigo by analysis of 85 patients dignosed as Meniere's disease, vestibular neuronitis, benign paroxysmal positional vertigo, labyrinthitis from January 1984 to April 1987. The results were as follows : 1) In the cases of Meniere's disease, the duration of treatment in same medical group was variable. 2) In the cases of vestibular neuronitis, the recovery was delayed with the use of sedatives. (p<0.05, K-W test) 3) In the cases of benign paroxysmal positional vertigo, the recovery was delayed with the use of sedatives(p<0.05, K-W test). 4) In the cases of labyrinthitis, the difference in the recovery did not happen among the medical groups.