Abstract
On the combination of 4-n-octyl-6-chlororesorcinol (O.C.R.) and 4-n-octylresorcinol (O.R.), marked potentiation was observed as to the ascaricidal power in vitro (1 : 1000) as well as to the clinical anthelmintic efficacy. The most efficient ratio of the mixture was 70 parts of O.C.R. to 30 parts of O.R. (equivalent to O.C.R. ca. 2mol : O.R. ca. 1 mol.), and its efficacy was obviously more excellent than hexylresorcinol. As to the oral toxicity to mice and the irritant action to the mucous membrane (on the conjunctiva of rabbits and human tongues), this mixture lay between O.R.and O.C.R., and was far weaker than hexylresorcinol. A 0.2 g per kg dose was almost harmless to the dog's gastric mucosa. Possible relationship between the potentiation of the ascaricidal property and some physical changes observed such as a lowering of interfacial tension of solution and a fall of melting point of the mixtures was discussed.
