Comparison

P21 vs GB-115

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

P21

Also: P021, Ac-DGGLAG-NH2

Preclinical

A synthetic peptide mimetic of CNTF (ciliary neurotrophic factor) designed for neurodegenerative disease. Promotes neurogenesis and reduces neuroinflammation.

CognitiveAnimal Studies
GB-115

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

Clinical Trials

A dipeptide anxiolytic and nootropic that acts as a CCK-1 (cholecystokinin) receptor antagonist. Developed in Russia with completed Phase 3 trials for anxiety. Users report significant improvements in focus, attention, and ADHD-like symptoms.

CognitiveHuman Trials

Key Comparison Insights

  • Both peptides belong to the Cognitive category, suggesting similar primary applications.
  • GB-115 has stronger research evidence (Human Trials) compared to P21 (Animal Studies).

Detailed Comparison

AttributeP21GB-115
CategoryCognitiveCognitive
FDA StatusNot FDA ApprovedNot FDA Approved
Clinical Status
Pre
I
II
III
IV
FDA
Pre
I
II
III
IV
FDA
Mechanism of ActionP21 acts as a CNTF small-molecule peptide mimetic. It enhances neurogenesis in the hippocampus, reduces tau phosphorylation, inhibits neuroinflammation, and improves synaptic plasticity. Designed to be orally bioavailable.GB-115 works by blocking central cholecystokinin-1 (CCK-1) receptors in the brain. CCK is involved in anxiety, panic responses, and cognitive modulation. By antagonizing these receptors, GB-115 reduces anxiety while improving attention, processing speed, and reaction time. It also modulates dopaminergic pathways involved in focus and motivation.
Common Dosing
Limited community data available
See research protocols
6 mg daily (2 mg three times daily)
2-3 times daily (morning, afternoon, evening)
AdministrationOral (nasal in some studies)Oral tablets or sublingual
Typical DurationOngoing supplementation in studies21+ days in clinical trials, effects noted by day 7
Best Time to TakeMorningMorning and throughout the day
Possible Side Effects
May vary by individual
  • Generally well-tolerated
  • Injection site reactions
  • Headache
  • Fatigue
  • Does NOT cause weight loss like native CNTF
  • +1 more
  • Generally well-tolerated
  • Minimal sedation compared to benzodiazepines
  • Headache (rare)
  • Mild gastrointestinal discomfort
  • No reported dependency or withdrawal
  • +2 more
Research SummaryStudies show cognitive improvement in Alzheimer's mouse models. Research demonstrates increased neurogenesis, reduced tau pathology, and improved learning/memory. Being developed for Alzheimer's and age-related cognitive decline.Clinical studies in patients with Generalized Anxiety Disorder (GAD) showed GB-115 (6mg/day) significantly improved reaction time, attention, and processing speed within 7 days of treatment. A 21-day trial with 31 patients demonstrated anxiolytic effects comparable to benzodiazepines without sedation or dependency. Currently in Phase II/III trials (NCT05586789) for anxiety disorders. Anecdotal reports suggest benefits for ADHD symptoms, though direct ADHD trials are pending.

Frequently Asked Questions: P21 vs GB-115

What is the difference between P21 and GB-115?

P21 is a cognitive peptide that a synthetic peptide mimetic of cntf (ciliary neurotrophic factor) designed for neurodegenerative disease. promotes neurogenesis and reduces neuroinflammation. GB-115 is a cognitive peptide that a dipeptide anxiolytic and nootropic that acts as a cck-1 (cholecystokinin) receptor antagonist. developed in russia with completed phase 3 trials for anxiety. users report significant improvements in focus, attention, and adhd-like symptoms. The main differences lie in their mechanisms of action and clinical applications.

Which is better, P21 or GB-115?

Neither is universally "better" - the choice depends on your specific goals. P21 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 P21 and GB-115 be used together?

Some peptide protocols combine multiple compounds for synergistic effects. However, using P21 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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Educational Information Only

This comparison of P21 and GB-115 is for educational purposes only. Neither this comparison nor any information on this site constitutes medical advice. Always consult with qualified healthcare providers before making decisions about peptides or other substances.