Side-by-side · Research reference

HexarelinvsSemax

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-MechanisticDraft12/39 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

Semax

Cognitive enhancer · Russian Pharma

200–600 mcg/doseIntranasalKaplan 2017

HumanMechanisticKaplan 2017

~30 minOnset

Intranasal · 2–3×/day during cognitive demand

01Mechanism of Action

Parameter

Hexarelin

Semax

Primary target

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

BDNF / NGF expression + monoamine modulationKaplan 2017

Pathway

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

↑ BDNF + NGF synthesis + 5-HT modulation → neuroplasticity + anxiolysis + cognitive enhancementKaplan 2017

Downstream effect

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

Improved memory + attention; reduced anxiety; neuroprotection in ischemiaKaplan 2017

Feedback intact?

Yes initially; tachyphylaxis with chronic useGhigo 1997

—

Origin

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

Synthetic 7-AA peptide derived from ACTH(4-7) with C-terminal Pro-Gly-Pro stabilising tailKaplan 2017

Antibody development

—

02Dosage Protocols

Parameter

Hexarelin

Semax

Standard dose

100–200 mcg per injectionSmith 1996

200–600 mcg / dose intranasalKaplan 2017

Frequency

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

2–3× per day during cognitive demand

Lower / starter dose

50 mcg per dose

100 mcg / dose

Evidence basis

Phase 1 / Phase 2 trialsSmith 1996 Ghigo 1997

Human-mechanistic + Russian clinicalKaplan 2017

Duration

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

10–14 day cycles, repeated PRN

Reconstitution

Bacteriostatic water

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

Timing

Pre-sleep + fasted preferred

Morning + early afternoon

Half-life

~70 minSemenistaya 2010

Short plasma; CNS effect lasts ~3–6 hr

04Side Effects & Safety

Parameter

Hexarelin

Semax

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

Nasal irritation

—

Mild burning or congestion (transient)

Sleep disruption

—

Late-day dosing may interfere with sleep

Headache

—

Uncommon, transient

Long-term safety

—

Limited Western RCT data

Absolute Contraindications

Hexarelin

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

Semax

·Pregnancy / breastfeeding

Relative Contraindications

Hexarelin

·Untreated diabetes
·Severe hyperprolactinemia

Semax

·Active psychiatric instability
·Concurrent strong stimulants

05Administration Protocol

Parameter

Hexarelin

Semax

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 — 2–3 sprays per nostril per dose. Tilt head slightly back.

3. Timing

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

Morning + early afternoon. Avoid evening (sleep disruption).

4. Storage

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

Refrigerate after reconstitution; light-protected.

5. Needle

29–31G, 4–8 mm insulin syringe.

Cycle on/off to avoid neurochemical adaptation.

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

Semax

+ Selank

Moderate

View Selank →

Semax (cognitive enhancer, BDNF/NGF) and Selank (anxiolytic + immune) form the canonical Russian "neuro stack" — both intranasal peptide bioregulators with complementary axes. Semax for cognitive demand; Selank for stress mitigation.

Semax: 200–600 mcg intranasal · morning + afternoon
Selank: 150–300 mcg intranasal · midday + early evening
Primary benefit: Cognitive enhancement + stress mitigation

Kaplan 2017 Zaderej 2014