The acute as well as the chronic toxicity of cetylpyridinium chloride has been determined. The MLD in rabbits following intravenous administration was 20 mgm. per kgm. Following oral administration this compound in an amount of 400 mgm. per kgm. killed one out of six rabbits. It was found that cetylpyridinium chloride was most toxic following intraperitoneal administration. In many cases death was delayed for from three to six days.
The results of the chronic toxicity tests indicate that cetylpyridinium chloride in the amounts administered for a period of four weeks has no significant harmful effects.
The irritant action on intact skin and mucous membranes was determined. Cetylpyridinium chloride exerted a "curare-like" action. It produced a central stimulation and a peripheral paralysis.