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Specimen Atlas of Research Peptides30 plates · MIT
Side-by-side · Research reference

GHRP-6vsSS-31

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

APhase 1Reviewed10/36 cited
BPhase 3Reviewed9/43 cited
GHRP-6
Hexapeptide GHRP · Strong appetite stimulant
100–200 mcgPer doseBowers 1990
Phase 1Evidence levelBowers 1990
~15 minHalf-lifeMalagón 1999
SQ · Multiple sites · 1–3×/day
SS-31
Cardiolipin-binding · Mitochondrial protective
40 mgDaily doseSzeto 2014
Phase 3Evidence levelSzilagyi 2009Szeto 2014
~3 hrHalf-life
SQ · Abdomen · Once daily

01Mechanism of Action

Parameter
GHRP-6
SS-31
Primary target
Ghrelin receptor (GHS-R1a)Bowers 1990
Cardiolipin in inner mitochondrial membraneSzeto 2014
Pathway
GHS-R1a → Gαq → Ca²⁺ → GH release; central appetite driveBowers 2002
Cardiolipin binding → cristae stabilisation → ETC integrity → reduced ROS + preserved ATP synthesisSzeto 2014Szilagyi 2009
Downstream effect
GH pulse + strong appetite stimulation; modest IGF-1 elevationBowers 2002
Mitochondrial bioenergetic preservation; cardio-, neuro-, and reno-protective effects in animal + clinical studiesSzeto 2014
Feedback intact?
Origin
Synthetic hexapeptide; first-generation GHRP from Bowers groupBowers 1990
Synthetic tetrapeptide D-Arg-Dmt-Lys-Phe-NH₂; cell-permeable, mitochondrial-selectiveSzeto 2014
Antibody development

02Dosage Protocols

Parameter
GHRP-6
SS-31
Standard dose
100–200 mcg per injectionBowers 1990
40 mg / day SQ (clinical trials)Szeto 2014
Anecdotal community range 5-10 mg/day. Phase 3 trials use 40 mg.
Frequency
1–3× per day
Once daily
Lower / starter dose
50 mcg per dose
5 mg / day (anecdotal)
Evidence basis
Phase 1 + clinical practiceBowers 1990
Multiple Phase 3 trials (Barth, AMD, ischemia-reperfusion)Szeto 2014Szilagyi 2009
Duration
8–12 weeks on / 4 off
Indefinite for mitochondrial disease; cycled for healthspan use
Reconstitution
Bacteriostatic water
Bacteriostatic water
Timing
Pre-meal preferred for appetite support
Morning fasted preferred; pre-workout for exercise-induced mitochondrial stress
Half-life
~3 h plasma; tissue uptake longer

04Side Effects & Safety

Parameter
GHRP-6
SS-31
Hunger
Pronounced — defining feature vs ipamorelin
Cortisol elevation
Mild
Prolactin elevation
Mild
Injection site reaction
Mild
Erythema, mild pruritus
Cancer risk
Contraindicated in active malignancy
Pregnancy / OB
Avoid
Avoid — insufficient data
GI symptoms
Nausea (uncommon)
Headache
Reported in some Phase 3 trials
Cardiovascular
Cardio-protective in studies; no signal of harm
Long-term safety
Phase 3 data over 24+ months; no major safety signalsSzeto 2014
Absolute Contraindications
GHRP-6
  • ·Active malignancy
  • ·Pregnancy / breastfeeding
SS-31
  • ·Pregnancy / breastfeeding
  • ·Hypersensitivity to peptide
Relative Contraindications
GHRP-6
  • ·Severe insulin resistance (appetite-driven caloric load)
SS-31
  • ·None established

05Administration Protocol

Parameter
GHRP-6
SS-31
1. Reconstitution
Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL.
Add bacteriostatic water per label. Light-protected handling.
2. Injection site
SQ — abdomen. Rotate sites.
SQ — abdomen or thigh. Rotate sites.
3. Timing
Pre-meal for appetite support; pre-sleep for GH alignment.
Morning fasted; pre-workout for exercise-augmented mitochondrial stress.
4. Storage
Lyophilised: room temp. Reconstituted: refrigerate ≤30 days.
Lyophilised: refrigerate, light-protected. Reconstituted: refrigerate ≤30 days.
5. Needle
29–31G, 4–8 mm insulin syringe.
29–31G, 4–8 mm insulin syringe.

06Stack Synergy

GHRP-6
— no documented stacks
SS-31
+ MOTS-c
Moderate
View MOTS-c

SS-31 and MOTS-c address mitochondrial decline through complementary axes. SS-31 protects existing mitochondrial structure (cardiolipin binding, cristae stabilisation). MOTS-c upregulates AMPK/PGC-1α, triggering biogenesis of new mitochondria. Together they pair preservation with renewal — anecdotally favoured in healthspan and post-cardio-event recovery protocols.

SS-31
5–10 mg SQ · daily morning
MOTS-c
5 mg SQ · 2× per week pre-workout
Primary benefit
Mitochondrial preservation + biogenesis