Semax is a designer drug, produced in Russia during the 1980s with the express intention of improving cognitive function.

Semax is a neuroactive peptide derived from corticotropin with the structure Pro8-Gly9-Pro10 ACTH(4-10). It shares a similar history, potency and chemical make-up with Noopept powder. It was initially pursued as a treatment for stroke victims suffering bran damage but was subsequently determined to promote significant cognitive enhancement in healthy individuals as well.
This nootropic stimulates the Central Nervous System and increases memory, focus, mental and physical performance, and analytical skills. It is regarded as much safer than other stimulants. Semax has been described as 1000 times stronger than Nootropil (Piracetam) which makes it similar in concentration to Noopept, Sunifiram and Unifiram.

In addition to stimulating the central nervous system (enhancing energy and metabolism) it works to modulate receptors for various brain chemicals: acetylcholine, dopamine, serotonin, adenosine, and histamine.

This results in the mental boost associated with the drug and allows users to perform brain tasks with increased vigor, clarity, and efficiency.

Semax may also have some use in reducing symptoms associated with stress and depression. At least one study has shown that (for those suffering from mental illness, at least) it had a calming, sedative effect that reduced many of their anxiety related issues.