Comparison

GB-115 vs NA-Semax Amidate

Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research

GB-115

Also: Ranquilon, N-phenylacetyl-L-prolylglycine ethyl ester

Clinical Trials

GB-115 is a synthetic dipeptide anxiolytic developed in Russia, chemically the amide of N-phenylhexanoyl-glycyl-L-tryptophan and described as a retro-analogue of cholecystokinin-4. Rather than acting like a benzodiazepine, it blocks cholecystokinin receptors, a different anti-anxiety route. It has been studied in animals and in a small pilot human study, but it is not an approved or widely available medication.

CognitiveHuman Trials
NA-Semax Amidate

Also: N-Acetyl Semax Amidate, NA-Semax

Clinical Trials

NA-Semax Amidate is the stabilized form of Semax, the Russian nootropic peptide derived from a fragment of ACTH. Same modification logic as the Selank variant: acetyl group at one end, amide at the other, both there to stop enzymes chewing it up before it does anything. It is the most widely used Semax variant in Western nootropic circles, largely on the strength of that stability argument.

CognitiveHuman Trials

Key Comparison Insights

  • Both peptides belong to the Cognitive category, suggesting similar primary applications.

Detailed Comparison

AttributeGB-115NA-Semax Amidate
CategoryCognitiveCognitive
FDA StatusNot FDA ApprovedNot FDA Approved
Clinical Status
Pre
I
II
III
IV
FDA
Pre
I
II
III
IV
FDA
Mechanism of ActionCholecystokinin (CCK) is a peptide that acts as a neurotransmitter in the brain, and activating its CCK-2 (also called CCK-B) and CCK-1 receptors tends to trigger anxiety and panic-like states. GB-115 works as an antagonist at these cholecystokinin receptors, meaning it occupies the receptor and blocks CCK from setting off that anxiety signaling. In animal work it specifically prevented anxiety provoked by CCK-4, which shares a pharmacological target with GB-115. This CCK-blocking mechanism is the proposed explanation for its calming effect, and it is distinct from the GABA system that classic sedatives act on.Semax is a synthetic analog of ACTH (4-10), a fragment of adrenocorticotropic hormone that has been stripped of hormonal activity while retaining effects on the brain. Its best-characterized action is a marked increase in BDNF and NGF expression in the hippocampus, which is the mechanistic basis for the memory and neuroprotection claims. It also modulates dopaminergic and serotonergic transmission, and affects the melanocortin system, which is thought to contribute to its effects on attention and motivation. Notably it does this without the HPA axis activation you would expect from something derived from ACTH, because the fragment lacks the region responsible for that. The acetylation and amidation slow degradation by peptidases, so more of the dose survives to act.
Common Dosing
6 mg daily (2 mg three times daily)
2-3 times daily (morning, afternoon, evening)
300-600 mcg daily (intranasal)
Once or twice daily, morning and early afternoon
AdministrationOral tablets or sublingualIntranasal is the standard and best-supported route, since it was developed as a nasal formulation
Typical Duration21+ days in clinical trials, effects noted by day 7Community protocols commonly report 2-4 week blocks
Best Time to TakeMorning and throughout the dayMorning, or morning and early afternoon if split
Possible Side Effects
May vary by individual
  • Generally well-tolerated
  • Minimal sedation compared to benzodiazepines
  • Headache (rare)
  • Mild gastrointestinal discomfort
  • No reported dependency or withdrawal
  • +2 more
  • Headache, the most commonly reported effect
  • Irritability or overstimulation, particularly with late dosing
  • Nasal irritation with intranasal use
  • Disturbed sleep if dosed in the evening
  • Flat mood reported after stopping in some accounts
  • +1 more
Research SummaryThe research record is real but thin and almost entirely from a single Russian group. In rodent studies (rats, BALB/c and C57Bl/6 mice), GB-115 reduced anxiety induced by CCK-4 and by yohimbine, with effects that varied by mouse strain, and it stayed effective after long-term dosing without producing tolerance or a withdrawal syndrome when stopped. Preclinical safety work has also been published. The only human data comes from a small pilot clinical study of 25 patients with generalized anxiety disorder given 6 mg daily for 21 days, where anxiety scores on the Hamilton scale fell substantially and fatigue scores improved. Importantly, that study was a single-arm pilot with no placebo or control group, so it cannot prove the drug caused the improvement. There are no large randomized controlled trials, no Western regulatory approval, and the evidence base remains preliminary.Semax has a genuine and reasonably large research base, concentrated in Russia, where it is a registered medicine used for ischemic stroke, cognitive impairment and optic nerve disorders. Animal work consistently supports the BDNF and NGF upregulation, and there is human clinical work in stroke recovery. The important caveat is the same as for Selank: this literature is largely Russian, much of it predates modern trial standards, replication in large Western randomized trials has not happened, and neither the FDA nor the EMA has assessed it. For the amidate variant specifically there is no independent published pharmacology comparing it to standard Semax in humans. The stability modification is chemically sound and widely used, and the assumption that it improves real-world effect is reasonable but unproven.

Frequently Asked Questions: GB-115 vs NA-Semax Amidate

What is the difference between GB-115 and NA-Semax Amidate?

GB-115 is a cognitive peptide that gb-115 is a synthetic dipeptide anxiolytic developed in russia, chemically the amide of n-phenylhexanoyl-glycyl-l-tryptophan and described as a retro-analogue of cholecystokinin-4. rather than acting like a benzodiazepine, it blocks cholecystokinin receptors, a different anti-anxiety route. it has been studied in animals and in a small pilot human study, but it is not an approved or widely available medication. NA-Semax Amidate is a cognitive peptide that na-semax amidate is the stabilized form of semax, the russian nootropic peptide derived from a fragment of acth. same modification logic as the selank variant: acetyl group at one end, amide at the other, both there to stop enzymes chewing it up before it does anything. it is the most widely used semax variant in western nootropic circles, largely on the strength of that stability argument. The main differences lie in their mechanisms of action and clinical applications.

Which is better, GB-115 or NA-Semax Amidate?

Neither is universally "better" - the choice depends on your specific goals. GB-115 is typically used for cognitive purposes, while NA-Semax Amidate is used for cognitive. Always consult with a healthcare provider to determine which may be appropriate for your situation.

Can GB-115 and NA-Semax Amidate be used together?

Some peptide protocols combine multiple compounds for synergistic effects. However, using GB-115 and NA-Semax Amidate together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.

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