N-phenylacetyl-L-prolylglycine ethyl ester, commonly known as Noopept, is a synthetic peptide compound structurally related to the racetam family of nootropics. Its use to support the "GABA body system" is not fully established, but there is some scientific investigation into its neuroprotective and cognitive-enhancing effects. Animal and in vitro studies have shown that Noopept can modulate several neurotransmitter systems, including glutamatergic and, to a lesser extent, GABAergic pathways. Some research suggests that Noopept may indirectly influence GABAergic transmission by increasing the expression of neurotrophic factors such as BDNF (Brain-Derived Neurotrophic Factor), which can impact overall neurotransmitter balance in the brain.

However, direct evidence supporting its specific action as a GABAergic modulator in humans is limited. Most studies have focused on its cognitive and neuroprotective effects rather than direct enhancement of GABAergic activity. There is also a lack of robust clinical trials evaluating its efficacy for supporting the GABA system specifically. Thus, while there is preliminary scientific exploration, the evidence is not strong or conclusive, and the current rating of 2 reflects the limited and indirect evidence available.