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Comparison

Sermorelin vs Spermidine

Side-by-side of Sermorelin 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.

Effects at a glance

Sermorelin

  • Synthetic 29-amino-acid GHRH fragment; FDA approved 1997 for pediatric GH deficiency as Geref
  • Voluntarily discontinued by Serono in 2008 for commercial reasons; not safety-related
  • Compounded by 503A/503B pharmacies for off-label adult anti-aging and body-composition use
  • Produces physiologic pulsatile GH release; ~10 to 20 minute plasma half-life
  • Standard anti-aging clinic protocol: 200 to 500 mcg subcutaneously pre-bed, often with ipamorelin
  • Banned by WADA under S2 (peptide hormones, growth factors)

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 Sermorelin Spermidine
Category peptide supplement
Also known as Sermorelin acetate, GRF 1-29, Geref, GHRH (1-29) NH2 spermidine trihydrochloride, wheat-germ-extract spermidine
Half-life (hr) 0.25 6
Typical dose (mg) 0.3 1.2
Dosing frequency 1-2x daily daily, typically morning with food
Routes subcutaneous oral
Onset (hr) 0.25 2
Peak (hr) 0.5 4
Molecular weight 3357.88 145.25
Molecular formula C149H246N44O42S C7H19N3
Mechanism Synthetic 29-amino-acid GHRH fragment that binds the GHRH receptor on pituitary somatotrophs to stimulate endogenous pulsatile GH synthesis and release while preserving the GH-IGF-1 negative feedback loop. 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 FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA OTC dietary supplement (wheat-germ extract has GRAS status in US)
WADA status banned allowed
DEA / Rx Rx only via compounding (no controlled-substance schedule) OTC supplement (not scheduled)
Pregnancy Category C (historical labeling); not recommended in pregnancy Insufficient data; not routinely recommended at supplemental doses
CAS 86168-78-7 124-20-9
PubChem CID 16129617 1102
Wikidata Q416620 Q411089

Safety profile

Sermorelin

Common side effects

  • injection-site pain or irritation
  • transient flushing
  • headache
  • vivid dreams (pre-bed dosing)

Contraindications

  • pregnancy
  • active malignancy
  • history of pituitary tumor
  • diabetic retinopathy (theoretical)
  • untreated hypothyroidism

Interactions

  • ipamorelin: synergistic GH release via parallel GHRH and ghrelin pathways; standard anti-aging clinic pairing(minor)
  • CJC-1295: pharmacologically redundant (both GHRH-pathway); typically not stacked(minor)
  • insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
  • corticosteroids: blunt GH response; reduce expected efficacy(moderate)
  • levothyroxine (untreated hypothyroidism): untreated hypothyroidism blunts GH response; correct thyroid first(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. Sermorelin is the right call when one of the conditionals below applies.

  • If your priority is growth-hormone axis, pick Sermorelin.
  • If your priority is post-training recovery, pick Sermorelin.
  • If your priority is focus or working memory, pick Spermidine.

Edge case: If you want to avoid FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA, 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 Sermorelin 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 Sermorelin and Spermidine?

Sermorelin 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, Sermorelin or Spermidine?

Sermorelin half-life is 0.25 hours; Spermidine half-life is 6 hours.

Can you stack Sermorelin with Spermidine?

Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.

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