Side-by-side · Research reference

SemaxvsSermorelin

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

AHuman-MechanisticDraft12/39 cited

BPhase 3Reviewed14/43 cited

Semax

Cognitive enhancer · Russian Pharma

200–600 mcg/doseIntranasalKaplan 2017

HumanMechanisticKaplan 2017

~30 minOnset

Intranasal · 2–3×/day during cognitive demand

Sermorelin

GHRH 1-29 fragment · Short-acting

100–500 mcgPer doseMolteno 2013

Phase 3Evidence levelWalker 1994 Molteno 2013

~12 minHalf-lifeMolteno 2013

SQ · Pre-sleep · 1×/day

01Mechanism of Action

Parameter

Semax

Sermorelin

Primary target

BDNF / NGF expression + monoamine modulationKaplan 2017

Pituitary GHRH receptorWalker 1994

Pathway

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

GHRH-R → Gαs → cAMP → PKA → GH vesicle exocytosisWalker 1994

Downstream effect

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

Pulsatile GH release; subsequent IGF-1 elevationMolteno 2013

Feedback intact?

—

Yes — short pulse preserves feedback

Origin

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

Unmodified active 29-AA fragment of human GHRH (1-44)Walker 1994

Antibody development

—

02Dosage Protocols

Parameter

Semax

Sermorelin

Standard dose

200–600 mcg / dose intranasalKaplan 2017

100–500 mcg per injectionMolteno 2013

Frequency

2–3× per day during cognitive demand

Once daily, pre-sleep

Lower / starter dose

100 mcg / dose

100 mcg per dose

Evidence basis

Human-mechanistic + Russian clinicalKaplan 2017

Phase 3 (Geref pediatric); clinical practiceWalker 1994 Molteno 2013

Duration

10–14 day cycles, repeated PRN

8–12 weeks per cycle

Reconstitution

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

Bacteriostatic water

Timing

Morning + early afternoon

Pre-sleep, fasted preferred

Half-life

Short plasma; CNS effect lasts ~3–6 hr

~12 min (plasma)Molteno 2013

Shorter than tesamorelin (~26 min) — simpler GHRH analogue.

04Side Effects & Safety

Parameter

Semax

Sermorelin

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

—

Pregnancy / OB

Avoid

Injection site reaction

—

Mild erythema, transient pain

Flushing / headache

—

Common transient effect

IGF-1 elevation

—

Modest at standard doses

Cancer risk

—

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

Glucose handling

—

Generally neutral

Absolute Contraindications

Semax

·Pregnancy / breastfeeding

Sermorelin

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

Relative Contraindications

Semax

·Active psychiatric instability
·Concurrent strong stimulants

Sermorelin

·Untreated diabetes

05Administration Protocol

Parameter

Semax

Sermorelin

1. Form

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

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

2. Administration

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

SQ — abdomen or thigh. Rotate sites.

3. Timing

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

Pre-sleep, fasted.

4. Storage

Refrigerate after reconstitution; light-protected.

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

5. Caveat

Cycle on/off to avoid neurochemical adaptation.

29–31G, 4–8 mm insulin syringe.

06Stack Synergy

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

Sermorelin

+ Ipamorelin

Strong

View Ipamorelin →

Sermorelin (GHRH analogue) and ipamorelin (selective GHRP) form the prototypical GHRH+GHRP dual-axis stack at the lowest cost. Both peak within 30 min and produce a sharp physiological GH pulse without cortisol/prolactin elevation.

Sermorelin: 200–300 mcg SQ · pre-sleep
Ipamorelin: 200–300 mcg SQ · same injection
Primary benefit: Pulsatile GH stimulation, recovery, body composition

Raun 1998 Walker 1994