Safety of large doses of vitamin D in theprevention and treatment of rickets in infancy

Abstract

I T WAS shown experimentally in 1928 that rickets in the rat could be prevented and treated with single massive doses of vitamin D, one thousand times the daily effective dose. ~ It was not until some years later, however, when purer preparations of vitamin D became available that it was possible to use larger than normal amounts of vitamin D clinically without producing toxic effects. Large doses of vitamin D may now be safely given to infants for prolonged periods of time if deemed necessary, or single massive doses of vitamin D may be administered which may be repeated on occasional intervals. The idea that large doses of vitamin D, without regard for other contributing factors, may be expected to cause calcification of the Mood vessels and soft tissues has become firmly entrenched in the medical mind as the result of two series of events. First, in about 1929 following the use of old viganto], a proprietary preparation of irradiated ergosterol, numerous clinical and experimental reports came out of Germany that this form of vitamin D was highly toxic and even fatal in larger doses. The exact doses used in terms of vitamin D units is not known, because this and similar preparations about this time differed not only in the potency of the irradiation product, but also in the concentration of vitamin D per cubic centimeter of the vehicle. 2 Subsequently, as the result of the work of Holtz and Schreiber (1930), GSttche and Kellner (1931), Windaus, Luttringhaus, and Bussc (1932), and Setz (1932), 3 it became known that the toxic and antirachitic effects of different irradiated ergosterol solutions did not run parallel and that the irradiation of ergosterol for short periods of time resulted chiefly in the production of tachysterol and ca]cifero], v whereas overirradiation produced toxisterol (Substance 248) and suprasterols, lacking in antirachitic action but strongly toxic.