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.

What are the side effects of GB-115?

Reported side effects of GB-115 include: Generally well-tolerated, Minimal sedation compared to benzodiazepines, Headache (rare), Mild gastrointestinal discomfort, No reported dependency or withdrawal, Limited long-term safety data, Not FDA approved.

What is the typical dosing for GB-115?

Doses observed in research studies. Common doses observed in research: 2 mg three times daily (6 mg/day total), Some users report 2-4 mg as needed. Duration: 21+ days in clinical trials, effects noted by day 7. Administration: Oral tablets or sublingual.

Cognitive

GB-115

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

Clinical Trials

Popular For

Anxiety, ADHD symptoms, focus, cognitive performance

Key Facts: GB-115

Category: Cognitive
FDA Status: Not FDA Approved
Clinical Status: Phase 3 Completed - Anxiety/adjustment disorders, not yet approved outside Russia
Administration: Oral tablets or sublingual
Typical Dose: 6 mg daily (2 mg three times daily)
Frequency: 2-3 times daily (morning, afternoon, evening)
Evidence Level: Human Trials
Duration: 21+ days in clinical trials, effects noted by day 7

Also Known As

Ranquilon, N-phenylacetyl-L-prolylglycine ethyl ester

Mechanism of Action

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.

Research Summary

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.

Clinical Status:Phase 3 Completed - Anxiety/adjustment disorders, not yet approved outside Russia

Trial Progress:Phase III

Pre

III

FDA

Dosing Information

Human Trials·Human studies conducted, not FDA approved

Typical DosingⓘDoses commonly used by people in practice, based on community reports and anecdotal experience.

Community experience

Common Dose

6 mg daily (2 mg three times daily)

Range

2-6 mg per day

Frequency

2-3 times daily (morning, afternoon, evening)

CCK-1 receptor antagonist from Russia. Clinical trial data showed 6 mg/day effective for 21-day cycles with cognitive improvements by day 7. Oral or sublingual administration. No sedation or dependency reported. Some users take 2-4 mg as needed for situational use.

Research DosingⓘDoses from published scientific studies and clinical trials. May include human or animal research.

Scientific studies

Doses observed in research studies

Doses from Studies

6 mg/day (2 mg three times daily)

Clinical Trial Data - GAD treatment study - 21 day protocol ↗

Duration

21+ days in clinical trials, effects noted by day 7

Administration

Oral tablets or sublingual

Timing & Administration

Best Time to Take

Morning and throughout the day

2-3 times daily for consistent effects

Food Recommendation

With or without food

Why This Timing?

Clinical trials used three times daily dosing (morning, afternoon, evening) for consistent receptor occupancy. Can be taken with or without food.

Possible Side Effects

Not everyone experiences these effects. Individual responses vary based on dosage, duration, and personal factors.

●Generally well-tolerated
●Minimal sedation compared to benzodiazepines
●Headache (rare)
●Mild gastrointestinal discomfort
●No reported dependency or withdrawal
●Limited long-term safety data
●Not FDA approved

References

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