GH Secretagogues: Tesamorelin vs CJC-1295 vs Sermorelin vs Ipamorelin
Growth hormone secretagogues are among the most popular peptides in the optimization space, but they differ significantly in mechanism, evidence base, FDA status, and clinical profile. Tesamorelin and Sermorelin are both GHRH analogs that stimulate GH release through the hypothalamic pathway, while Ipamorelin is a ghrelin-mimetic secretagogue, and CJC-1295 is a modified GHRH analog with an extended half-life. Understanding these distinctions is essential for informed conversations with your clinician about which approach best fits your goals.
These four peptides all raise growth hormone, but they're not interchangeable. Tesamorelin is the only one with current FDA approval (for HIV visceral fat). CJC-1295 is long-acting and convenient. Sermorelin is the gentle, physiologic classic. Ipamorelin is the clean ghrelin-receptor trigger — often paired with CJC-1295 for synergy. Pick based on evidence requirements, injection tolerance, and which metabolic side effects you want to avoid.
Tesamorelin
An FDA-approved GHRH analog used to reduce visceral fat in HIV-associated lipodystrophy.
CJC-1295
A growth hormone-releasing hormone analog that stimulates the pituitary gland to produce more growth hormone.
Sermorelin
A growth hormone-releasing hormone analog that was previously FDA-approved for diagnosing GH deficiency in children.
Ipamorelin
A selective growth hormone secretagogue that stimulates GH release without significantly affecting cortisol or prolactin.
| Category | Tesamorelin | CJC-1295 | Sermorelin | Ipamorelin |
|---|---|---|---|---|
| Drug Class | GHRH analog (44 amino acids) | Modified GHRH analog (29 aa) with DAC | GHRH analog (29 amino acids) | Ghrelin-mimetic GH secretagogue (5 aa) |
| Primary Mechanism | Binds GHRH receptor on pituitary somatotrophs | Binds GHRH receptor; DAC extends half-life via albumin binding | Binds GHRH receptor, mimics natural GHRH | Binds ghrelin/GHS receptor (GHS-R1a) on pituitary |
| FDA Status | FDA-approved (Egrifta®) for HIV lipodystrophy | Not FDA-approved; available via compounding | Previously FDA-approved (Geref®), now discontinued | Not FDA-approved; available via compounding |
| Evidence Level | Strong — multiple Phase III RCTs | Moderate — human PK/PD data, limited clinical trials | Moderate — historical clinical use, some RCTs | Moderate — Phase II data, well-characterized PK |
| Half-Life | 26 minutes (requires daily dosing) | ~8 days (with DAC); ~30 min without DAC | 11–16 minutes (requires daily dosing) | ~2 hours (longer than natural ghrelin) |
| GH Pulse Pattern | Amplifies natural pulsatile release | With DAC: sustained GH elevation; without DAC: pulsatile | Mimics natural pulsatile GH release | Stimulates discrete GH pulses |
| Effect on Cortisol | Minimal | Minimal | Minimal | No significant cortisol increase (selective) |
| Effect on Prolactin | Minimal | Minimal | Minimal | No significant prolactin increase (selective) |
| Effect on Hunger/Ghrelin | Minimal appetite effect | Minimal appetite effect | Minimal appetite effect | Mild transient hunger possible (ghrelin pathway) |
| Key Clinical Benefits | Visceral fat reduction (proven), improved lipid profile, body composition | Sustained GH/IGF-1 elevation, body composition, recovery | GH restoration, anti-aging, sleep quality, body composition | Clean GH pulse, sleep quality, recovery, body composition |
| Common Pairing | Often used as monotherapy | Frequently paired with Ipamorelin for synergy | Sometimes paired with Ipamorelin or MK-677 | Frequently paired with CJC-1295 (no DAC) for synergy |
| Administration | Subcutaneous injection, daily | Subcutaneous injection, 2–3x/week (with DAC) or daily (no DAC) | Subcutaneous injection, daily (typically before bed) | Subcutaneous injection, daily (typically before bed) |
| Safety Profile | Well-studied; injection site reactions, arthralgia, edema | Moderate data; injection site reactions, water retention, headache | Moderate data; facial flushing, injection site pain, headache | Moderate data; well-tolerated, mild injection site reactions |
| Ideal Candidate | Those with visceral adiposity or seeking FDA-backed GH therapy | Those wanting sustained GH elevation with less frequent dosing | Those seeking physiologic GH restoration with historical clinical precedent | Those wanting selective, clean GH pulses without cortisol/prolactin effects |
In depth
Two classes working on the same axis
These four compounds all end up raising growth hormone, but they belong to two different mechanistic classes. Tesamorelin, CJC-1295, and Sermorelin are all GHRH analogs — they bind the growth-hormone-releasing-hormone receptor on the pituitary, effectively amplifying the signal your hypothalamus is already sending. Ipamorelin is a ghrelin-mimetic — it binds a parallel receptor (GHS-R1a) on the same pituitary cells, triggering GH release through a different door. The two classes are complementary rather than redundant, which is why a GHRH analog paired with Ipamorelin produces more GH than either alone.
What separates the three GHRH analogs
Among the GHRH analogs, the practical differentiator is half-life and FDA status. Sermorelin is the shortest-acting (11–16 minutes) — it mimics natural GHRH almost exactly, which is elegant physiologically but demands strict daily-before-bed dosing to catch the sleep GH pulse. Tesamorelin is moderately acting (~26 minutes) and carries the only current FDA approval in the class, specifically for HIV-associated visceral fat — the strongest evidence base but the narrowest approved indication. CJC-1295 with DAC is long-acting (6–8 days) thanks to a linker that binds albumin, giving you weekly dosing convenience at the cost of sustained (rather than pulsatile) GH exposure — which some clinicians consider a feature and others a concern.
Why Ipamorelin is the selective option
Ipamorelin's defining feature is what it doesn't do. Earlier ghrelin-mimetics (GHRP-2, GHRP-6, hexarelin) all stimulate GH but also spike cortisol, prolactin, and hunger — inconvenient for anyone trying to recomp. Ipamorelin is the clean one: GH release without the collateral axis activation. That's the reason it displaced the older GHRPs as the default ghrelin-side partner in GH peptide protocols.
What the evidence actually supports
Tesamorelin has the strongest clinical evidence — Phase III RCTs demonstrating visceral fat reduction and lipid improvements in HIV lipodystrophy patients. CJC-1295, Sermorelin, and Ipamorelin all have moderate human pharmacodynamic data showing they raise GH and IGF-1 as expected, but none has the outcome-trial depth of Tesamorelin. Sermorelin was historically FDA-approved (as Geref) but was withdrawn in 2008 for commercial rather than safety reasons. The rest are compounded.
Bottom line
If you specifically want FDA-backed therapy with strong evidence, Tesamorelin is the answer — especially if visceral fat is the target. If you want sustained elevation with weekly convenience, CJC-1295 with DAC. If you want the most physiologic approach with the longest clinical track record, Sermorelin. If you want the cleanest secretagogue effect without metabolic side effects, Ipamorelin — almost always paired with a GHRH analog rather than used alone. The single most popular combination is CJC-1295 (no DAC) + Ipamorelin before bed, because it hits both receptor pathways while preserving pulsatile GH release. Whichever approach, clinician supervision with IGF-1 monitoring is essential.
These peptides are often used together. See our stack profiles for combination details.