Biorhythms in toxicology and pharmacology. II. infradian biorhythms and general discussion.

In man circaseptidian (weekly) rhythm has been established in certain employements where a delayed pulmonary allergic reaction is observed. Circatrigintan (monthly) rhythms related to the biological effects of the rotation of the moon around the earth or of the rotation of the sun around its axis have not been definitely pointed out in man. The demonstration of a circannual (seasonal) biorhythmicity of responses to drugs and toxins requires long runs of observations (5-7 years). However circannual, as well as infrannual rhythms, should not be dismissed as they are consequences of biometeorological factors the actions of which at least for temperature on toxic reactions are admitted. Besides the influences of endogenous factors such as sex and aging perturbate the endocrinological modulations of these biorhythms and complicate the scope of such a research. The cyclic action mechanism of therapeutic and toxic agents appears to be a direct impact on intrinsic enzymatic rhythms of different periods entrained by the physical, chemical and principally psychophysiological factors of man's environment.