Canadian Journal of Anesthesia, Vol 9, 399-407, Copyright © 1962 by Canadian Anesthesiologists' Society

A Comparative Study of Eleven Anti-emetic Drugs in Dogs

¹ Department of Anaesthesia, University of Saskatchewan, and University Hospital, Saskatoon, Saskatchewan

Using a cross-over technique in which each animal served as its own control, it was found that not all anti-emetics are equally effective against both apomorphine-induced and copper-sulphate-induced vomiting. Trimethoxybenzamide and the phenothiazines, with the exception of promazine, were highly effective in controlling apomorphine-induced emesis; they were effective to a lesser degree,but still satisfactorily, against the emetic challenge of copper sulphate. Dimenhydrinate,cyclizine, and L-hyoscine were entirely ineffective in controlling apomorphine-induced vomiting but were reasonably satisfactory in the effect of copper sulphate, in that they afforded protection similar to trimethoxybenzamide and the phenothiazine derivatives.

It is therefore concluded that in the postoperative period,when multiple factors are at work in the production of emesis, trimethoxybenzamide or one of the phenothiazines be used to control emesis unless there is a clear indication that vomiting is entirely of gastrointestinal origin, in which case one of the other agents may be successfully employed.

Our findings were in keeping with our clinical impressions. The doses required for some of the phenothiazines to control vomiting in dogs were so large that one would surmise that if the same dosé relationship exists in man, marked side-effects would be produced in addition to satisfactory control of emesis.

Note:

Presented at the Annual Meeting, Canadian Anaesthetists' Society, at Montebello, P.Q., May 14–17, 1962.

Financial assistance from the following is gratefully acknowledged: Hoffman-La Roche Limited, Montreal, P.Q.; Poulenc Limited, Montreal, P.Q.; Sandoz Pharmaceuticals, Dorval, P.Q.; and Schering Corporation Limited, Montreal, P.Q.