Growth hormone and muscle
Peptides that prompt the body to release growth hormone, growth hormone itself, and the growth factors downstream of it. Tesamorelin is the one FDA-approved growth hormone releaser.
Which of these has the most human evidence? See Best Peptides for Muscle Growth, Ranked by Human Evidence.
GHRH analogues (act on the GHRH receptor)
aka CJC-1295 with DAC · CJC-1295 without DAC · Modified GRF (1-29)
Investigated as a long-acting growth hormone-releasing hormone analogue to raise GH and IGF-I. Reached Phase 2 and was discontinued; never approved for any indication.
Limited human dataResearch use only
aka Egrifta · Egrifta WR · Egrifta SV
Approved for reducing excess visceral abdominal fat in people with HIV-associated lipodystrophy.
Strong human evidenceFDA-approved · prescription only
aka GHRH(1-29)NH2 · Geref · Sermorelin acetate
Marketed to adults for sleep, body composition and aging. Its former FDA approvals, as Geref, were for growth hormone deficiency in children and a 0.05 mg diagnostic test; both are discontinued.
Limited human dataUnapproved drug
GHRH analogues (act on the GHRH receptor): side by side
Doses for unapproved compounds are common practice, not trial-established.
| Compound | Main use | Evidence | Usual dose | US status |
|---|---|---|---|---|
| CJC-1295 | Investigated as a long-acting growth hormone-releasing hormone analogue to raise GH and IGF-I. Reached Phase 2 and was discontinued; never approved for any indication. | Limited human data | 100-300 mcg, once daily, 5 days a week (5 days on, 2 off), usually the no-DAC form | Research use only |
| Tesamorelin | Approved for reducing excess visceral abdominal fat in people with HIV-associated lipodystrophy. | Strong human evidence | FDA label | FDA-approved · prescription only |
| Sermorelin | Marketed to adults for sleep, body composition and aging. Its former FDA approvals, as Geref, were for growth hormone deficiency in children and a 0.05 mg diagnostic test; both are discontinued. | Limited human data | 200-600 mcg, once nightly; most protocols run 5-7 nights a week, some as 5 days on/2 off | Unapproved drug |
Secretagogues (act on the ghrelin receptor)
aka NNC 26-0161 · Aib-His-D-2-Nal-D-Phe-Lys-NH2
Investigated for postoperative ileus, reaching Phase 2 before being discontinued for insufficient efficacy. Marketed to consumers for growth hormone release, an application never approved anywhere.
Limited human dataResearch use only
aka Ibutamoren · Ibutamoren mesylate · L-163,191
Developed as an oral, non-injectable alternative to peptide growth hormone secretagogues. Published trials in healthy older adults and obese men found it raised growth hormone and IGF-1 and increased fat-free mass; FDA references a hip-fracture trial that was stopped early. Marketed to consumers as a research chemical for muscle and recovery, a use never approved by any regulator.
Limited human dataResearch use only
aka Growth Hormone Releasing Peptide-2 · Pralmorelin · KP-102
Sold to consumers as a growth-hormone-release research chemical for muscle and recovery use, an application never approved anywhere. Historically investigated as a pituitary growth-hormone stimulus and diagnostic agent.
Limited human dataResearch use only
aka Growth Hormone Releasing Peptide-6 · GHRP6 · His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
One of the original growth hormone-releasing peptides, studied since the 1980s as a pituitary GH secretagogue. Marketed to consumers for muscle and recovery goals, an application never approved anywhere.
Limited human dataResearch use only
aka Examorelin · HEXA
Investigated since the 1990s as a growth hormone-releasing peptide (GHRP), including for growth-hormone stimulation testing. Sold to consumers as a research chemical for muscle and recovery use, an application with no controlled human trial behind it.
Limited human dataResearch use only
Secretagogues (act on the ghrelin receptor): side by side
Doses for unapproved compounds are common practice, not trial-established.
| Compound | Main use | Evidence | Usual dose | US status |
|---|---|---|---|---|
| Ipamorelin | Investigated for postoperative ileus, reaching Phase 2 before being discontinued for insufficient efficacy. Marketed to consumers for growth hormone release, an application never approved anywhere. | Limited human data | 100-300 mcg, once nightly on 5 days a week in physician-supervised protocols, up to three times daily on an empty stomach in less structured use | Research use only |
| MK-677 (Ibutamoren) | Developed as an oral, non-injectable alternative to peptide growth hormone secretagogues. Published trials in healthy older adults and obese men found it raised growth hormone and IGF-1 and increased fat-free mass; FDA references a hip-fracture trial that was stopped early. Marketed to consumers as a research chemical for muscle and recovery, a use never approved by any regulator. | Limited human data | 12.5-25 mg, once daily by mouth; the published 2008 trial dosed each morning, while compounding-pharmacy protocols commonly move dosing to before bed | Research use only |
| GHRP-2 | Sold to consumers as a growth-hormone-release research chemical for muscle and recovery use, an application never approved anywhere. Historically investigated as a pituitary growth-hormone stimulus and diagnostic agent. | Limited human data | 100-300 mcg, 2 to 3 times daily, on an empty stomach, 5 days a week (5 on, 2 off) | Research use only |
| GHRP-6 | One of the original growth hormone-releasing peptides, studied since the 1980s as a pituitary GH secretagogue. Marketed to consumers for muscle and recovery goals, an application never approved anywhere. | Limited human data | 100-300 mcg, 2 to 3 times daily, on an empty stomach, spaced at least 3-4 hours apart | Research use only |
| Hexarelin | Investigated since the 1990s as a growth hormone-releasing peptide (GHRP), including for growth-hormone stimulation testing. Sold to consumers as a research chemical for muscle and recovery use, an application with no controlled human trial behind it. | Limited human data | 80-160 mcg, once or twice daily (morning and/or before bed), on an empty stomach | Research use only |
Growth hormone and growth factors
aka Somatropin · rHGH · 191-amino acid recombinant human growth hormone
Marketed to consumers for body recomposition, recovery and anti-aging in adults who do not have a diagnosed growth hormone deficiency. The identical molecule, somatropin, is FDA-approved by prescription for defined deficiency and wasting conditions - see the "Where approved somatropin fits" section on the main guide for that distinction.
Limited human dataResearch use only
aka Long R3 IGF-1 · Long-R3-IGF-1
Originally engineered as a laboratory reagent - an IGF-1 variant with reduced binding to IGF-binding proteins, used to study IGF-1 signalling in cell culture. Sold to consumers as a research chemical for muscle growth, a use with no controlled human trial behind it.
Animal / lab onlyResearch use only
aka Des(1-3)IGF-1 · IGF-1 Des(1-3) · Truncated IGF-1
Originally isolated and studied as a naturally occurring IGF-1 fragment in laboratory pharmacology, used to probe IGF-1 receptor signalling with reduced interference from binding proteins. Sold to consumers as a research chemical for localised, site-specific muscle growth, a use with no controlled human trial behind it.
Animal / lab onlyResearch use only
aka Mechano Growth Factor · IGF-1Ec · Non-pegylated MGF
Marketed to consumers as a peptide injected directly into a trained muscle immediately after exercise, for local muscle repair and growth. No completed human trial has tested it for this or any outcome.
Animal / lab onlyResearch use only
aka Pegylated Mechano Growth Factor · PEGylated MGF · IGF-1Ec peptide analogue
Marketed to consumers for muscle repair and growth after resistance training. Never approved for human use; FDA states it has identified no human exposure data on it by any route.
Animal / lab onlyResearch use only
aka FST · Follistatin-344 · FST-344
The body's own brake on activin and myostatin signalling, studied academically as a gene-therapy payload for muscle-wasting disease. Sold separately, as an injected research-chemical protein, for grey-market muscle-building use that its own human trials have never tested.
Animal / lab onlyResearch use only
Growth hormone and growth factors: side by side
Doses for unapproved compounds are common practice, not trial-established.
| Compound | Main use | Evidence | Usual dose | US status |
|---|---|---|---|---|
| HGH 191AA | Marketed to consumers for body recomposition, recovery and anti-aging in adults who do not have a diagnosed growth hormone deficiency. The identical molecule, somatropin, is FDA-approved by prescription for defined deficiency and wasting conditions - see the "Where approved somatropin fits" section on the main guide for that distinction. | Limited human data | 333-1333 mcg, Once daily (split into a morning and evening dose above roughly 3 IU/day), subcutaneous | Research use only |
| IGF-1 LR3 | Originally engineered as a laboratory reagent - an IGF-1 variant with reduced binding to IGF-binding proteins, used to study IGF-1 signalling in cell culture. Sold to consumers as a research chemical for muscle growth, a use with no controlled human trial behind it. | Animal / lab only | 20-50 mcg, once daily | Research use only |
| IGF-1 DES | Originally isolated and studied as a naturally occurring IGF-1 fragment in laboratory pharmacology, used to probe IGF-1 receptor signalling with reduced interference from binding proteins. Sold to consumers as a research chemical for localised, site-specific muscle growth, a use with no controlled human trial behind it. | Animal / lab only | 20-120 mcg, on training days only, about 4-5 times a week, not on rest days | Research use only |
| MGF | Marketed to consumers as a peptide injected directly into a trained muscle immediately after exercise, for local muscle repair and growth. No completed human trial has tested it for this or any outcome. | Animal / lab only | 100-400 mcg, Immediately post-workout, 2-3 times a week (training days only) | Research use only |
| PEG-MGF | Marketed to consumers for muscle repair and growth after resistance training. Never approved for human use; FDA states it has identified no human exposure data on it by any route. | Animal / lab only | 200-400 mcg, 2-3 times a week, post-workout | Research use only |
| Follistatin | The body's own brake on activin and myostatin signalling, studied academically as a gene-therapy payload for muscle-wasting disease. Sold separately, as an injected research-chemical protein, for grey-market muscle-building use that its own human trials have never tested. | Animal / lab only | 100-500 mcg, 2 to 4 times a week | Research use only |