Glossary
Nootropic
Nootropic, coined by Giurgea in 1972, has five original criteria most marketed compounds fail. What the term means in peptide research today.
Nootropic was coined by Corneliu Giurgea in 1972 to describe piracetam and compounds like it. His definition was specific: enhancement of learning and memory, resistance of learned behaviours to disruptive conditions, protection of the brain against physical or chemical injury, improvement of tonic cortical control mechanisms, and — the criterion most often ignored — an absence of the sedative, stimulant or toxic effects typical of psychotropic drugs.
Why the definition matters in a catalog
Almost nothing marketed as a nootropic today satisfies all five criteria, and the word carries no regulatory or mechanistic meaning. In peptide research it functions as a shelving category, grouping molecules with entirely different targets: melanocortin-derived ACTH fragments such as Semax, the tuftsin analogue Selank, angiotensin-IV-derived Dihexa, and the ampakine-adjacent and racetam small molecules. Their proposed mechanisms range from BDNF expression and HGF/c-Met signalling to GABAergic modulation.
Because the category is heterogeneous and much of the peptide literature is Russian-language rodent work plus small clinical series, comparative claims should be framed by study type rather than by category. None of this material is approved in the US; it is supplied research use only.
Related terms and material
neurotrophin · intranasal. Reference material: nootropic peptides, Semax, Selank. Further reading: peptides for focus and memory research.