Comparison
GHRP-6 vs Spermidine
Side-by-side of GHRP-6 and Spermidine. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
GHRP-6
First-generation hexapeptide ghrelin-receptor agonist. Pioneered the GHS-R1a pathway in the 1980s. Produces the strongest hunger response among GHRPs and a mo.
Spermidine
Spermidine supplement benefits cover autophagy induction, longevity signals, and cognition. Wheat germ extract data, doses, and human trials reviewed.
Effects at a glance
GHRP-6
- •First-generation hexapeptide ghrelin-receptor agonist; foundational to the GHRP class
- •Strongest appetite stimulation of any synthetic GHRP at equivalent GH doses
- •Produces measurable cortisol and prolactin rise alongside the GH pulse
- •Anecdotal protocols use 100 to 200 mcg subcutaneously 2 to 3 times daily on an empty stomach
- •Largely superseded by ipamorelin (cleaner profile) and GHRP-2 (stronger pulse) for body-composition use
- •Banned by WADA under S2; detection methods validated in accredited labs
Spermidine
- •Endogenous polyamine that induces autophagy via EP300 acetyltransferase inhibition and TFEB activation
- •Concentrated in wheat germ, soybeans, aged cheese, and mushrooms; ~10 to 15 mg/day in Mediterranean diets
- •Eisenberg 2016 reported dietary spermidine extended mouse lifespan and improved cardiac function
- •Wirth 2018 pilot (n=28) reported cognitive signal at 0.9 mg/day in older adults at risk for dementia
- •Larger Wirth 2019 follow-up (n=85) did not replicate the memory benefit at 12 months
- •Generally regarded as safe at supplemental doses; food-source position is reassuring
Side-by-side
| Attribute | GHRP-6 | Spermidine |
|---|---|---|
| Category | peptide | supplement |
| Also known as | Growth Hormone Releasing Peptide 6, SKF-110679, Histidyl-D-Tryptophyl-Alanyl-Tryptophyl-D-Phenylalanyl-Lysinamide | spermidine trihydrochloride, wheat-germ-extract spermidine |
| Half-life (hr) ↗ | 0.5 | 6 |
| Typical dose (mg) ↗ | 0.1 | 1.2 |
| Dosing frequency | 2-3x daily | daily, typically morning with food |
| Routes | subcutaneous, intravenous | oral |
| Onset (hr) | 0.25 | 2 |
| Peak (hr) | 0.5 | 4 |
| Molecular weight | 872.44 | 145.25 |
| Molecular formula | C46H56N12O6 | C7H19N3 |
| Mechanism | Hexapeptide agonist of GHS-R1a (ghrelin receptor). Suppresses hypothalamic somatostatin and stimulates pituitary somatotrophs, with strong central NPY/AgRP appetite signaling and modest cortisol and prolactin release. | Induces macroautophagy via inhibition of EP300 histone acetyltransferase and activation of TFEB-mediated lysosomal biogenesis. Substrate for hypusination of eIF5A, required for translation of mitochondrial respiration proteins. |
| Legal status | Not FDA approved; research-use-only grey market; banned by WADA | OTC dietary supplement (wheat-germ extract has GRAS status in US) |
| WADA status | banned | allowed |
| DEA / Rx | Not scheduled (research chemical) | OTC supplement (not scheduled) |
| Pregnancy | Insufficient data; not recommended | Insufficient data; not routinely recommended at supplemental doses |
| CAS | 87616-84-0 | 124-20-9 |
| PubChem CID | 9919072 | 1102 |
| Wikidata | Q5519921 | Q411089 |
Safety profile
GHRP-6
Common side effects
- intense hunger
- water retention
- vivid dreams
- head pressure or flushing
- tingling at injection site
- transient lethargy
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- uncontrolled diabetes
- prolactin sensitivity
Interactions
- CJC-1295: synergistic GH release; commonly co-administered(minor)
- sermorelin: additive GH release via parallel GHRH and ghrelin pathways(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: blunt GH response and amplify cortisol load(moderate)
Spermidine
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- wheat-germ allergy or celiac disease (for wheat-germ-extract products)
- active cancer (theoretical)
- pregnancy and lactation (insufficient data)
Interactions
- DFMO (difluoromethylornithine): competing polyamine metabolism; do not combine without oncology guidance(moderate)
Which Should You Take?
Spermidine comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. GHRP-6 is the right call when one of the conditionals below applies.
- → If your priority is growth-hormone axis, pick GHRP-6.
- → If your priority is appetite regulation, pick GHRP-6.
- → If your priority is healthspan extension, pick Spermidine.
- → If your priority is focus or working memory, pick Spermidine.
Edge case: If you want to avoid research-only / gray-market sourcing, Spermidine is the more accessible choice.
Default choice: Spermidine. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for GHRP-6 only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between GHRP-6 and Spermidine?
GHRP-6 and Spermidine differ in category (peptide vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, GHRP-6 or Spermidine?
GHRP-6 half-life is 0.5 hours; Spermidine half-life is 6 hours.
Can you stack GHRP-6 with Spermidine?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper