Studies on the low toxicity of reduced iron, B.P. 1932.

Reduced iron, B.P. 1932, an old form of medicinal metallic iron powder, was given by mouth to albino rats. Measurable toxic effects were not produced until the dose reached 10 g./kg. body weight, which is 10 times the LD(50) of iron similarly given as ferrous sulfate. Death occurred at three days and after from doses of 60 to 100 g./kg. and was due to hemoconcentration and vascular congestion of the liver and kidneys resulting from absorption of iron through an inflamed gastrointestinal mucosa. Larger doses produced death in one to three days from bowel obstruction due to impaction of iron in the stomach and intestines. The results suggest that reduced iron is the least toxic of all iron medicinal preparations and that re-investigation of its therapeutic value is warranted.