Comparison
Ipamorelin vs Sermorelin
Side-by-side of Ipamorelin and Sermorelin. 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.
Ipamorelin
Ipamorelin peptide benefits: selective ghrelin-receptor GHRP, 200 to 300 mcg dosage, GH pulse without cortisol or prolactin rise, CJC-1295 stack vs sermorelin.
Sermorelin
Sermorelin peptide therapy uses a 29-amino-acid GHRH analog to raise endogenous GH. Dosing, half-life, sermorelin vs ipamorelin, and safety.
Effects at a glance
Ipamorelin
- •Pentapeptide GHS-R1a agonist with the cleanest selectivity profile in the GHRP class
- •Minimal cortisol and prolactin elevation at standard doses (substantially less than GHRP-2 or hexarelin)
- •~2 hour plasma half-life, longest of the synthetic GHRPs
- •Largest human safety database (~600 participants in Helsinn's postoperative ileus phase 2)
- •Standard pairing for CJC-1295 no-DAC at 200 to 300 mcg subcutaneously 2 to 3 times daily
- •Banned by WADA under S2; never reached registration despite phase 2b development
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)
Side-by-side
| Attribute | Ipamorelin | Sermorelin |
|---|---|---|
| Category | peptide | peptide |
| Also known as | NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2 | Sermorelin acetate, GRF 1-29, Geref, GHRH (1-29) NH2 |
| Half-life (hr) ↗ | 2 | 0.25 |
| Typical dose (mg) ↗ | 0.2 | 0.3 |
| Dosing frequency | 2-3x daily | 1-2x daily |
| Routes | subcutaneous, intravenous | subcutaneous |
| Onset (hr) | 0.25 | 0.25 |
| Peak (hr) | 1 | 0.5 |
| Molecular weight | 711.86 | 3357.88 |
| Molecular formula | C38H49N9O5 | C149H246N44O42S |
| Mechanism | Selective GHS-R1a agonist that stimulates pulsatile GH release with minimal cortisol or prolactin co-activation. Suppresses hypothalamic somatostatin and stimulates pituitary somatotrophs. | 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. |
| Legal status | Not FDA approved; advanced through phase 2b in postoperative ileus before discontinuation; research-use-only grey market; banned by WADA | FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA |
| WADA status | banned | banned |
| DEA / Rx | Not scheduled (research chemical) | Rx only via compounding (no controlled-substance schedule) |
| Pregnancy | Insufficient data; not recommended | Category C (historical labeling); not recommended in pregnancy |
| CAS | 170851-70-4 | 86168-78-7 |
| PubChem CID | 11338566 | 16129617 |
| Wikidata | Q1666741 | Q416620 |
Safety profile
Ipamorelin
Common side effects
- injection-site irritation
- vivid dreams
- transient mild head pressure
- occasional headache
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- uncontrolled diabetes
Interactions
- CJC-1295: synergistic GH release via parallel GHRH and ghrelin pathways; standard pairing(minor)
- sermorelin: additive GH release; functionally similar pairing to CJC-1295 with shorter GHRH half-life(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: blunt GH response; reduce expected efficacy(moderate)
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)
Which Should You Take?
Sermorelin comes out ahead for most readers on the criteria we weight: 3 catalogued goals, FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA, with a Tier-A outcome catalogued. Ipamorelin is the right call when one of the conditionals below applies.
- → If your priority is body composition, pick Ipamorelin.
- → If your priority is healthspan extension, pick Sermorelin.
- → If your priority is growth-hormone axis, pick Sermorelin.
Edge case: Half-lives differ materially (Ipamorelin ~2 hr vs Sermorelin ~0.25 hr). Ipamorelin reaches steady state faster; Sermorelin is easier to dial in if tolerability is uncertain.
Default choice: Sermorelin. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Ipamorelin 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 Ipamorelin and Sermorelin?
Ipamorelin and Sermorelin differ in category (peptide vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Ipamorelin or Sermorelin?
Ipamorelin half-life is 2 hours; Sermorelin half-life is 0.25 hours.
Can you stack Ipamorelin with Sermorelin?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper