In acute experience on two types of rodents (rats and mice), at the intraperitoneal, subcutaneous and oral ways of introduction the acute toxicity of new bioactive substance from oxyethylidendiphosphonate germanates — medgerm is studied. It is established that this substance at intraperitoneal and subcutaneous ways of introduction belongs to compounds with little toxicity, and at the peroral way of introduction — to compounds with low toxicity in both types of animals, that testifies to perspective of further screening researches of this new compound.