Comparison

Selank vs GB-115

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

Selank

Also: Selanc, TP-7

Clinical Trials

Selank is a synthetic seven-amino-acid peptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) built from the natural immune peptide tuftsin, with a small chemical tweak to make it last longer in the body. It was developed in Russia as an anti-anxiety and nootropic agent and is approved there for generalized anxiety disorder, but it has no FDA or EMA approval and almost no Western clinical data. The pitch is calm and focus without the sedation, dependence, or withdrawal that come with benzodiazepines.

CognitiveHuman Trials
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

Key Comparison Insights

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

Detailed Comparison

AttributeSelankGB-115
CategoryCognitiveCognitive
FDA StatusNot FDA ApprovedNot FDA Approved
Clinical Status
Pre
I
II
III
IV
FDA
Pre
I
II
III
IV
FDA
Mechanism of ActionSelank seems to work through several overlapping systems rather than one tidy target. It influences GABA signaling, the brain's main calming neurotransmitter system, which likely accounts for its anti-anxiety effect. It also slows the breakdown of enkephalins, the body's own opioid-like peptides involved in mood and stress, which is a mechanism entirely different from benzodiazepines or SSRIs. Animal work additionally points to effects on serotonin and dopamine balance and on BDNF, a growth factor tied to learning and neuron health. These pathways are well documented in rodents; the picture in humans is inferred rather than directly measured.Cholecystokinin (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.
Common Dosing
250-500 mcg intranasal 2-3x daily
2-3x daily, intranasal
6 mg daily (2 mg three times daily)
2-3 times daily (morning, afternoon, evening)
AdministrationIntranasal spray (most common), subcutaneous injectionOral tablets or sublingual
Typical Duration14-21 days typical21+ days in clinical trials, effects noted by day 7
Best Time to TakeMorning or as needed for anxietyMorning and throughout the day
Possible Side Effects
May vary by individual
  • Generally well-tolerated
  • Nasal irritation (spray)
  • Headache
  • Nausea
  • Fatigue
  • +3 more
  • Generally well-tolerated
  • Minimal sedation compared to benzodiazepines
  • Headache (rare)
  • Mild gastrointestinal discomfort
  • No reported dependency or withdrawal
  • +2 more
Research SummaryMost of the rigorous data is preclinical and Russian. In rodents, Selank shows consistent anxiety-reducing and mild cognitive effects, and one PMC-indexed study found it enhanced diazepam's anti-anxiety effect under chronic stress. The main human clinical reference is a Russian comparative trial by Zozulia, Neznamov, and colleagues in patients with generalized anxiety disorder and neurasthenia, reporting that Selank's anxiolytic effect was comparable to the benzodiazepine medazepam on standard rating scales, with added anti-fatigue benefits and changes in enkephalin activity. The honest caveat: that trial was relatively small, the published English abstract gives qualitative results rather than hard effect sizes and p-values, and it has not been replicated by independent Western groups. So the evidence supports a real but modestly studied anxiolytic, mostly validated within the regulatory system that approved it.The 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.

Frequently Asked Questions: Selank vs GB-115

What is the difference between Selank and GB-115?

Selank is a cognitive peptide that selank is a synthetic seven-amino-acid peptide (thr-lys-pro-arg-pro-gly-pro) built from the natural immune peptide tuftsin, with a small chemical tweak to make it last longer in the body. it was developed in russia as an anti-anxiety and nootropic agent and is approved there for generalized anxiety disorder, but it has no fda or ema approval and almost no western clinical data. the pitch is calm and focus without the sedation, dependence, or withdrawal that come with benzodiazepines. 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. The main differences lie in their mechanisms of action and clinical applications.

Which is better, Selank or GB-115?

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

Can Selank and GB-115 be used together?

Some peptide protocols combine multiple compounds for synergistic effects. However, using Selank and GB-115 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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