The work contains information concerning mechanisms of action of antibodies in extremely small doses (ESD) to endogenic regulators of organism’s functions. The following medicines are discussed: Proproten and Tenoten which deal with brain specific S-100 protein and have psychotropic activity; Impasa which deals with NO-synthasa and regulates mail reproductive function; Anaferon for adults and children which deals with interferon gamma and has immunomodulating and antivirus activity; Artrofon which deals with tumor necrosis factor alfa and is used in artrology as a perspective remedy in pathogenic diseases therapy.