Cognitive peptides

This smaller family is used for focus, mood, and mental resilience. The evidence is thinner and comes from a different part of the world, so read it with extra care.

Semax (SEE-max) and Selank (SELL-ank) are the two you will hear about most. Both were developed in Russia, where they are actually approved and prescribed, which is unusual for compounds in this space. Semax is used for focus, memory, and recovery from mental fatigue. Selank leans toward calm, taking the edge off anxiety without the grogginess of typical anti-anxiety drugs. They are often taken as a nasal spray rather than injected, since they can reach the brain that way.

The catch is the evidence base. Most of the research is Russian. Much of it is in animals or small human studies that have not been widely repeated elsewhere. That does not make the reports fake, but it does mean the rest of the world has not confirmed them, so keep your confidence modest.

A few other cognitive peptides circulate, like Dihexa, with even less human data behind them. Treat those as experimental.