To the Editor:—
The suggestion recently made in this section of The Journal (144:1283 [Dec. 9] 1950) by Drs. Rudolph, Park and Hamilton, that dimenhydrinate administered rectally be used for the control of postanesthesia vomiting prompts us to cite our experience in treating this condition. Contrary to the opinion of these correspondents, we believe that sufficient pharmacologic information is already available to serve as a valuable guide to therapy in emesis.Dimenhydrinate (dramamine®) is the 8-chlorotheophylline salt of diphenhydramine (benadryl®). Pharmacologic studies have shown that the theophylline portion of the molecule is ineffective in preventing apomorphine-induced emesis in dogs (White, J. M.; Freedman, D.; McCawley, E. L., and Gray, W. D.: Federation Proc.9:325 [April] 1950) and that the active portion of the dimenhydrinate molecule is the diphenhydramine component. Apomorphine-induced emesis is controlled with 1 mg. of diphenhydramine and 2 mg. of dimenhydrinate per kilogram of body weight.