In the group of immunomodulators isolated preparations of animal, microbial, yeast and synthetic origin, having a specific ability to stimulate immune processes and to activate immune cells (T - and b-lymphocytes) and the additional factors of immunity (macrophages, etc.). Increase in the overall resistance of the organism may in some or the other extent, be under the influence of some stimulating and tonic agents (caffeine, ginseng, etc.), vitamins, dibazola, derivatives of pyrimidine — methyluracil, pentoksila (accelerate regeneration, intensifitsiruetsa leucopoiesis), derivatives of nucleic acids and biogenic drugs, generally referred to as adaptogens. The ability of these drugs to increase the resistance of the body, speed up the process of regeneration has formed the basis for wide application in complex therapy of indolent regenerative processes, infectious, infectious-inflammatory and other diseases. It was particularly significant in recent years, the study of the immunological properties of endogenous compounds — lymphokines, interferons (therapeutic efficacy of several drugs — Poludan, Arbidol, etc. — explain to some extent the fact that they stimulate the formation of endogenous interferon, i.e., they are interferonogenami).

The most important role in the functioning of cellular and humoral immunity plays a thymus gland (thymus). It occurs the differentiation of stem cells into lymphocytes, and the secretion of specific substances (hormones) that influence the development and maturation of certain cells of the lymphoid tissue. The thymus gland identified a number of polypeptide hormones (thymosin, homeostatic timusny hormone, timopoetin I and II, timusny humoral factor) and steroid (timosterin) structure. We received a number of extractive products (Timalin, Taktivin, timoptin, Vilozen), used as Immunostimulants; they all contain the above-mentioned hormones of the thymus gland (including an alpha thymosin) and are largely similar to each other for action. From another organ of the immune system — bone marrow — derived drug-activin. To synthetic Immunostimulants include levamisole, a number of peptide adjuvants — alpha-glutamyl-tryptophan (Timogen), etc.