DSIP is a well-known neuromodulator and natural somnogenic nonapeptide with many other physiological functions. It is typically found in the brain and easily passes the blood-brain barrier. It is mainly prescribed for the treatment of pain condition, alcohol and opioid withdrawal, CRH and stress related symptoms, low testosterone (via stimulation of LH), and even sometimes as an antioxidant and anti-oncogenic protein. It has been discovered and heavily studied for over 40 years, yet, the mechanism of action is still complex and not well organized. The results of studies of DSIP and its analogues over a period of 30 years since its discovery enable one to state with confidence that DSIP is a unique member of the family of peptide neuromodulators. It exhibits a pronounced stress protective action and decreases stress-induced metabolic and functional disorders in human and animal organisms exposed to a variety of stresses. Some of the effects of the peptide are accomplished through the modulating action on central regulatory processes, owing to the systemic antioxidant action, the modulating influence on the activity of GABAergic, glutamatergic, and other neuronal systems. It also works on the expression of early response genes in brain structures, and on the activity of biosynthetic and proteolytic processes.