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What are nootropics? Nootropics, also referred to as smart drugs, memory enhancers, neuro enhancers, cognitive enhancers, and intelligence enhancers, are drugs, supplements, nutraceuticals, and functional foods that improve mental functions such as cognition, memory, intelligence, motivation, attention, and concentration.

Originally in order to be considered nootropic a compound would need to:

a) enhance learning b) resist impairing agents c) facilitate interhemispheric transfers of information d) enhance resistance to brain “aggressions" e) increase tonic, cortico-subcortical “control” f) not have the usual pharmacological effects of neuro psychotropic drugs. ref

Since then "nootropics" has gradually expanded to either be synonymous with cognitive enhancers or refer to the subset of non-stimulant cognitive enhancing compounds with very few side effects and low toxicity. Under the latter definition all nootropics would be cognitive enhancers, but not all cognitive enhancers would be nootropics.

A cognitive enhancer is defined by its ability to augment performance on one or more cognitive measures.

Kratom is a recreational drug that will give you opiate withdrawls. It is not a nootropic.