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Specimen Atlas of Research Peptides81 plates · MIT
Side-by-side · Research reference

GonadorelinvsSemax

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

AFDA-ApprovedHUMAN-REVIEWED7/61 cited
BHuman-MechanisticAUTO-DRAFTED12/39 cited
Gonadorelin
GnRH Analogue · Diagnostic & Therapeutic
90 minPulsatile interval
73%Ovulation restorationTadesse 2026
2–4 minPlasma half-life
IV / SQ · Pulsatile Pump (Therapeutic) · Single Bolus (Diagnostic)
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
Gonadorelin
Semax
Primary target
GnRH receptors on anterior pituitary gonadotropes
BDNF / NGF expression + monoamine modulationKaplan 2017
Pathway
GnRH → Pituitary gonadotrope → LH/FSH secretion → Gonadal steroidogenesisSharma 2026
↑ BDNF + NGF synthesis + 5-HT modulation → neuroplasticity + anxiolysis + cognitive enhancementKaplan 2017
Downstream effect
Pulsatile LH/FSH release stimulates testicular testosterone or ovarian estradiol/progesterone synthesis; initiates folliculogenesis and spermatogenesisRobin 2026Sharma 2026
Improved memory + attention; reduced anxiety; neuroprotection in ischemiaKaplan 2017
Feedback intact?
Yes — pulsatile delivery preserves negative feedback loops; continuous exposure desensitizes receptors
Origin
Synthetic decapeptide (pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2) identical to native hypothalamic GnRH
Synthetic 7-AA peptide derived from ACTH(4-7) with C-terminal Pro-Gly-Pro stabilising tailKaplan 2017
Antibody development

02Dosage Protocols

Parameter
Gonadorelin
Semax
Diagnostic test (pituitary function)
100 mcg IV or SQ bolus
Measure baseline LH/FSH, then 30/60/90 min post-injection. Normal response: LH ≥2× baseline.
Therapeutic (hypothalamic hypogonadism)
5–20 mcg IV bolus every 90–120 minutes
Requires portable pulsatile pump. Dose individualized to achieve normal gonadotropin pulsatility.Robin 2026
Pulsatile interval
90 minutes (females) · 120 minutes (males)
Mimics physiological GnRH pulse frequency.
Route
IV preferred (therapeutic) · SQ acceptable (diagnostic)
Duration
Continuous until pregnancy achieved or fertility goals met
3–6 month courses typical for ovulation induction.
10–14 day cycles, repeated PRN
Evidence basis
RCT / Expert consensus
Human-mechanistic + Russian clinicalKaplan 2017
Half-life
2–4 minutes (plasma)
Necessitates frequent pulsatile administration.
Short plasma; CNS effect lasts ~3–6 hr
Alternative protocols
Exogenous gonadotropins (hCG/hMG) often preferred due to convenience vs pump requirement
Standard dose
200–600 mcg / dose intranasalKaplan 2017
Frequency
2–3× per day during cognitive demand
Lower / starter dose
100 mcg / dose
Reconstitution
Pre-formulated nasal spray (commercial); research vial: bacteriostatic water
Timing
Morning + early afternoon

03Metabolic / Fat Loss Evidence

Parameter
Gonadorelin
Semax
Fat loss mechanism
None — gonadorelin acts exclusively on reproductive axis
Indirect metabolic effects
Restoration of sex hormones may normalize body composition in hypogonadal states
Effect mediated by downstream testosterone/estradiol, not GnRH itself.

04Side Effects & Safety

Parameter
Gonadorelin
Semax
Injection site reaction
Erythema, irritation (pulsatile pump catheter site)
Headache
Common with bolus administration
Uncommon, transient
Nausea / abdominal discomfort
Transient, dose-related
Ovarian hyperstimulation syndrome (OHSS)
Risk with ovulation induction protocols; monitor follicular development via ultrasound
Multiple gestation
Increased risk with fertility protocols (twins ~10–15%)
Anaphylaxis
Rare hypersensitivity reaction
Pump malfunction / infection
Mechanical failure or catheter-site infection with long-term IV pump use
Receptor desensitization
Continuous (non-pulsatile) exposure paradoxically suppresses gonadotropinsRobin 2026
Nasal irritation
Mild burning or congestion (transient)
Sleep disruption
Late-day dosing may interfere with sleep
Long-term safety
Limited Western RCT data
Pregnancy / OB
Avoid
Absolute Contraindications
Gonadorelin
  • ·Pregnancy (except therapeutic infertility protocols)
  • ·Hypersensitivity to gonadorelin or excipients
  • ·Hormone-dependent tumors (prostate, breast) — risk of tumor stimulation via sex hormone elevation
Semax
  • ·Pregnancy / breastfeeding
Relative Contraindications
Gonadorelin
  • ·Ovarian cysts or PCOS (monitor for OHSS)
  • ·Pituitary adenoma or other sellar mass (may worsen with gonadotropin surge)
Semax
  • ·Active psychiatric instability
  • ·Concurrent strong stimulants

05Administration Protocol

Parameter
Gonadorelin
Semax
1. Diagnostic protocol
Administer 100 mcg IV or SQ bolus. Draw baseline LH/FSH, then at 30, 60, 90 minutes. Normal response: LH ≥2× baseline, FSH modest rise. Blunted response suggests pituitary pathology; exaggerated response may indicate primary hypogonadism.
Pre-formulated nasal spray (commercial) or research vial reconstituted with bacteriostatic water.
2. Therapeutic pump setup (pulsatile)
Requires programmable infusion pump with IV catheter. Set pulse interval to 90 min (females) or 120 min (males). Bolus dose 5–20 mcg per pulse. Pump worn continuously; catheter site rotated every 48–72 hrs to prevent infection.
Intranasal — 2–3 sprays per nostril per dose. Tilt head slightly back.
3. Reconstitution
Lyophilised gonadorelin reconstituted with sterile saline or provided diluent. Typically 0.8–3.2 mg dissolved in 8 mL for pump reservoir. Solution stable 7–14 days refrigerated.
Morning + early afternoon. Avoid evening (sleep disruption).
4. Monitoring
For fertility protocols: ultrasound follicular tracking + serial estradiol/LH measurements. Adjust pulse dose to achieve mid-follicular LH 5–10 IU/L. Ovulation confirmed by progesterone rise or ultrasound.
Refrigerate after reconstitution; light-protected.
5. Timing
Pulsatile therapy initiated at any point in cycle. Diagnostic test performed in morning (higher baseline LH). For ovulation induction, treatment begins early follicular phase.
Cycle on/off to avoid neurochemical adaptation.

06Stack Synergy

Gonadorelin
+ hCG (Human Chorionic Gonadotropin)
Multi-pathway
View hCG (Human Chorionic Gonadotropin)

In hypogonadotropic hypogonadism protocols, gonadorelin restores pituitary LH/FSH pulsatility, while exogenous hCG directly stimulates Leydig cells (acting as LH mimetic) to maintain testosterone production. This dual approach ensures both central axis restoration and immediate gonadal steroidogenesis, preventing testicular atrophy during fertility treatment. hCG's longer half-life (24–36 hrs) complements gonadorelin's pulsatile short-acting profile.

Gonadorelin
5–10 mcg IV every 120 min (pulsatile pump)
hCG
1500–2000 IU SQ · 2–3× per week
Duration
12–24 weeks for spermatogenesis induction
Primary benefit
Fertility restoration in hypothalamic hypogonadism with maintained testicular function
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