The potentialities of some antihistaminics in preanaesthetic medication

A detailed study has been carried out on the potentialities of antazoline and chlorpheneramine (C.P.M.) in preanaesthetic medication. It included a determination of their sedative action, effects on cardiovascular system and any possible anticholinergic and antiarrhythmic properties. Both drugs depressed spontaneous activity in mice. Antazoline produced hypotension in chloralosed dogs and spinal cats (a peripheral action). Both produced a negative inotropic action on isolated rabbit's heart. On rat's auricle antazoline produced a positive chronotropic action while C.P.M. produced a negative chronotropic action. Both drugs could protect the heart against adrenaline induced arrhythmias during chloroform and halothane anaesthesia. Their anticholinergic properties were demonstrated by studies on isolated rabbit's heart and intestine as well as on isolated guinea pig's ileum.