The great importance of chemical elements in the economy of the body also indicates their importance as medicinal agents. Many of these elements have been used in the treatment of serious diseases since ancient times. However, the high toxicity of most chemical agents has led to the fact that modern medicine has either completely stopped using many valuable chemical drugs or has reduced their use to a minimum. This is particularly true of arsenic. Therefore, the removal of "side effects" from medicinal drugs is a constant challenge for modern pharmacology. However, this is not always possible due to the increased sensitivity of some people to certain elements. In this regard, homeopathy is in a more favorable position due to the use of medications in microdoses. It can even use highly toxic chemicals in its practice.