Comparison
Ipamorelin vs Testosterone
Side-by-side of Ipamorelin and Testosterone. 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.
Testosterone
Testosterone replacement therapy for hypogonadism: TRAVERSE 2023 cardiovascular data, cypionate dosing, body composition gains, Schedule III status.
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
Testosterone
- •Primary androgen; FDA approved for hypogonadism with confirmed deficiency and symptoms
- •Testosterone Trials (2016) showed sexual function and bone density improvements in older hypogonadal men
- •TRAVERSE 2023 (n=5,246) found non-inferiority on MACE versus placebo, with higher AF and PE rates
- •Schedule III controlled substance in US; WADA banned in sport
- •Aromatizes to estradiol; converts to DHT via 5-alpha reductase; both metabolites matter clinically
- •Erythrocytosis (HCT above 54%) affects 5 to 25% of users and is the most common dose-limiting effect
Side-by-side
| Attribute | Ipamorelin | Testosterone |
|---|---|---|
| Category | peptide | hormone |
| Also known as | NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2 | TRT, testosterone replacement therapy, testosterone cypionate, testosterone enanthate, Androgel, Testim |
| Half-life (hr) ↗ | 2 | 192 |
| Typical dose (mg) ↗ | 0.2 | 150 |
| Dosing frequency | 2-3x daily | weekly to twice-weekly (cypionate/enanthate IM or SC); daily (topical, oral); every 3 to 6 months (pellet) |
| Routes | subcutaneous, intravenous | intramuscular, subcutaneous, topical, buccal, subcutaneous (pellet), oral |
| Onset (hr) | 0.25 | 24 |
| Peak (hr) | 1 | 72 |
| Molecular weight | 711.86 | 288.42 |
| Molecular formula | C38H49N9O5 | C19H28O2 |
| Mechanism | Selective GHS-R1a agonist that stimulates pulsatile GH release with minimal cortisol or prolactin co-activation. Suppresses hypothalamic somatostatin and stimulates pituitary somatotrophs. | Androgen receptor agonist driving anabolic gene transcription in muscle, bone, brain, and androgen-sensitive tissue. Aromatized to estradiol and 5-alpha-reduced to DHT, both with distinct downstream effects. |
| Legal status | Not FDA approved; advanced through phase 2b in postoperative ileus before discontinuation; research-use-only grey market; banned by WADA | Schedule III controlled substance (US); WADA banned |
| WADA status | banned | banned |
| DEA / Rx | Not scheduled (research chemical) | Schedule III |
| Pregnancy | Insufficient data; not recommended | Category X; contraindicated in pregnancy (virilizing effect on female fetus) |
| CAS | 170851-70-4 | 58-22-0 |
| PubChem CID | 11338566 | 6013 |
| Wikidata | Q1666741 | Q150726 |
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)
Testosterone
Common side effects
- erythrocytosis
- acne
- oily skin
- fluid retention
- increased body hair
- fertility suppression
- injection-site reactions
Contraindications
- active prostate cancer
- active breast cancer
- untreated severe sleep apnea
- untreated severe BPH
- uncontrolled heart failure
- polycythemia at baseline
Interactions
- warfarin: may potentiate anticoagulant effect; monitor INR(moderate)
- insulin: may improve insulin sensitivity; monitor glucose in diabetics(moderate)
- 5-alpha reductase inhibitors (finasteride): blocks DHT conversion; reduces some androgen effects(moderate)
- aromatase inhibitors (anastrozole): lowers estradiol; risk of over-suppression(moderate)
Which Should You Take?
Testosterone comes out ahead for most readers on the criteria we weight: 3 catalogued goals, controlled substance, oral dosing, with a Tier-A outcome catalogued. Ipamorelin is the right call when one of the conditionals below applies.
- → If your priority is growth-hormone axis, pick Ipamorelin.
- → If your priority is post-training recovery, pick Ipamorelin.
- → If your priority is hormonal optimization, pick Testosterone.
- → If your priority is sexual function, pick Testosterone.
Edge case: If you cannot self-administer injections, Testosterone is the only oral option in this pair.
Default choice: Testosterone. 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 Testosterone?
Ipamorelin and Testosterone differ in category (peptide vs hormone), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Ipamorelin or Testosterone?
Ipamorelin half-life is 2 hours; Testosterone half-life is 192 hours.
Can you stack Ipamorelin with Testosterone?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper