Side-by-side · Research reference

HexarelinvsSelank

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 1Reviewed19/45 cited

BHuman-MechanisticDraft11/40 cited

Hexarelin

Hexapeptide GHRP · Cardio-tropic

100–200 mcgPer doseSmith 1996

Phase 1Evidence levelGhigo 1997

~70 minHalf-lifeSemenistaya 2010

SQ · Multiple sites · 1–3×/day

Selank

Anxiolytic + Cognitive · Russian Pharma

150–300 mcg/doseIntranasalZaderej 2014

HumanMechanisticZaderej 2014 Medvedev 2007

~30 minOnset

Intranasal · 2–3×/day during stress / cognitive demand

01Mechanism of Action

Parameter

Hexarelin

Selank

Primary target

Ghrelin receptor (GHS-R1a) + cardiac CD36Smith 1996 Ghigo 1997

Monoamine system (serotonin / GABA modulation) + immunomodulation via tuftsin domainZaderej 2014

Pathway

GHS-R1a → Gαq → Ca²⁺ → GH release. CD36 engagement → direct cardio-tropic actionGhigo 1997

Tuftsin-derived immune signaling + CNS monoamine modulation → reduced anxiety + improved mood / cognitionMedvedev 2007

Downstream effect

Strong GH pulse + IGF-1 elevation; cardio-protective effects in animal MI modelsGhigo 1997

Anxiolytic + cognitive enhancement; immunomodulation via increased IL-6 + IFN-γMedvedev 2007 Zaderej 2014

Feedback intact?

Yes initially; tachyphylaxis with chronic useGhigo 1997

No GABA-receptor binding; no dependence reportedMedvedev 2007

Origin

Synthetic hexapeptide His-D-2-Methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂Smith 1996

Synthetic 7-AA peptide derived from human tuftsin (immune-system tetrapeptide)Zaderej 2014

Antibody development

—

02Dosage Protocols

Parameter

Hexarelin

Selank

Standard dose

100–200 mcg per injectionSmith 1996

150–300 mcg / dose intranasalZaderej 2014

Frequency

1–2× per day max (tachyphylaxis with chronic 3× daily)

2–3× per day during stress

Lower / starter dose

50 mcg per dose

75 mcg / dose

Evidence basis

Phase 1 / Phase 2 trialsSmith 1996 Ghigo 1997

Human-mechanistic + Russian clinical trialsMedvedev 2007

Duration

4–8 weeks on / 4–8 weeks off (tachyphylaxis mitigation)

10–14 day cycles, repeated as needed

Reconstitution

Bacteriostatic water

Pre-formulated nasal spray (commercial); research vial: bacteriostatic water

Timing

Pre-sleep + fasted preferred

Morning + early afternoon preferred

Half-life

~70 minSemenistaya 2010

Short (minutes plasma); CNS effect lasts ~3 hr

04Side Effects & Safety

Parameter

Hexarelin

Selank

Cortisol elevation

Modest at high dosesGhigo 1997

—

Prolactin elevation

Modest at high dosesGhigo 1997

—

Hunger

Strong appetite increase via ghrelin agonism

—

Tachyphylaxis

Receptor desensitisation with chronic dosingGhigo 1997

—

Cardiac effects

Direct cardio-tropic; potential benefit in MI but unstudied in humansGhigo 1997

—

IGF-1 elevation

Strong; monitor with chronic high-dose use

—

Cancer risk

Contraindicated in active malignancy (GH/IGF-1 axis)

—

Pregnancy / OB

Avoid

Avoid — insufficient data

Nasal irritation

—

Mild burning or congestion (transient)

Sedation

—

None — distinct from benzodiazepinesMedvedev 2007

Dependence / withdrawal

—

None reported in clinical useZaderej 2014

Cognitive impairment

—

None — opposite effect (enhancement)

Allergic reaction

—

Rare hypersensitivity

Long-term safety

—

Limited Western RCT data

Absolute Contraindications

Hexarelin

·Active malignancy
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

Selank

·Pregnancy / breastfeeding
·Hypersensitivity to peptide

Relative Contraindications

Hexarelin

·Untreated diabetes
·Severe hyperprolactinemia

Selank

·Active autoimmune disease (theoretical via immunomodulation)

05Administration Protocol

Parameter

Hexarelin

Selank

1. Reconstitution

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL = 250 mcg per 0.1 mL.

Pre-formulated nasal spray (commercial) or research vial reconstituted with bacteriostatic water.

2. Injection site

SQ — abdomen or thigh. Rotate sites.

Intranasal — 1–3 sprays per nostril per dose. Tilt head slightly back.

3. Timing

Pre-sleep + fasted preferred. Cycle on/off to avoid tachyphylaxis.

Morning + early afternoon for cognitive demand; PRN for acute anxiety.

4. Storage

Lyophilised: room temp, light-protected. Reconstituted: refrigerate ≤30 days.

Refrigerate after reconstitution; ≤30 days. Light-protected.

5. Needle

29–31G, 4–8 mm insulin syringe.

Avoid co-administration with strong sedatives or other anxiolytics initially.

06Stack Synergy

Hexarelin

+ CJC-1295 (no DAC)

Strong

View CJC-1295 (no DAC) →

Hexarelin (GHRP) + CJC-1295-no-DAC (GHRH analogue) is the higher-amplitude variant of the standard GHRH+GHRP stack. Hexarelin produces a stronger pulse than ipamorelin but with cortisol + prolactin signal — choose this stack for maximum GH amplitude when side-effect tolerance is acceptable. Cycle aggressively.

Hexarelin: 100 mcg SQ · pre-sleep
CJC-1295 (no DAC): 100 mcg SQ · same injection
Primary benefit: Maximum GH pulse amplitude (with side-effect signal)

Smith 1996 Teichman 2006

Selank

— no documented stacks