PE-22-28

Cognitive Research compound (not approved for human use)

Spadin-derived peptide (TREK-1 channel blocker) · also known as PE 22-28, Spadin analog

For reference only — not medical advice. Figures are commonly reported values compiled from published sources and may be wrong or out of date. Many compounds listed are not approved for human use. Talk to a licensed clinician before using any compound.

PE-22-28 is a shortened analog of spadin, a natural peptide released from the sortilin receptor propeptide. It was engineered to keep spadin's block of the TREK-1 potassium channel while being more stable in the body. Everything known about it comes from laboratory and animal studies.

Commonly reported dosing by vial size

Frequency: Once daily, subcutaneous · Half-life: Not well characterized in humans

Vial size (2 sizes)8 mg10 mg

8 mg vial + 2.5 mL → 3.2 mg per mL

Diluent: bacteriostatic water (as commonly reported)

Volume shown keeps the same concentration as the 10 mg vial; no specific figure was found for this size.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
2.5 mL of bacteriostatic water is added slowly down the inside wall of the 8 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 3.2 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Below about 2 units on a U-100 syringe at this concentration; not reliably measurable.	50 mcg	0.016 mL	1.6 (warning)
Standard	100 mcg	0.031 mL	3.1
Higher	200 mcg	0.063 mL	6.3

⚠ Under 2 units on a U-100 syringe at this concentration, which is hard to measure reliably.

Open in calculator (8 mg + 2.5 mL)

10 mg vial + 3 mL → 3.33 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 10 mg vial is commonly reconstituted with 3 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
3 mL of bacteriostatic water is added slowly down the inside wall of the 10 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 3.33 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Below about 2 units on a U-100 syringe at this concentration; not reliably measurable.	50 mcg	0.015 mL	1.5 (warning)
Standard	100 mcg	0.03 mL	3
Higher	200 mcg	0.06 mL	6

⚠ Under 2 units on a U-100 syringe at this concentration, which is hard to measure reliably.

Open in calculator (10 mg + 3 mL)

Storage

Before mixing: Lyophilized vials are commonly stored frozen (-20 °C).

After mixing: Reconstituted solution is commonly kept refrigerated (2-8 °C) and protected from light.

Commonly used within 28 days of mixing.

How it works

By inhibiting TREK-1 channels, PE-22-28 is thought to change neuronal excitability and serotonergic signaling in ways that mimic antidepressant responses seen in rodents.

Researched for

Studied in rodents for antidepressant-like behavior with faster onset than conventional agents.
Investigated as a more stable alternative to spadin in TREK-1 inhibition assays.

Notes

No human clinical trials are known; the dosing figures are community-reported and extrapolated.
Regimens in the reference are weight-independent micro-doses, which are small volumes on a U-100 syringe.