Best Peptides for Muscle Growth: What the Evidence Shows

The short answer

We found no peptide with good human evidence for building muscle in healthy adults. The growth-hormone-releasing peptides most often sold for this purpose have been shown to raise hormone levels, a lab marker, but not to increase muscle. The one FDA-approved peptide in this family, tesamorelin, is approved to reduce abdominal fat in people with HIV, not to build muscle. Every peptide covered below is prohibited in competitive sport.

On this page

Peptides that raise growth hormone are marketed for muscle, but raising a hormone level is not the same as building muscle. Here is what has actually been measured in people, which products are FDA-approved for what, and what athletes need to know.

The ranking, by strength of evidence

How do we decide what is “best”?

“Best” means best evidence. For muscle growth we look for a randomized, controlled trial in people that measured muscle mass or strength, not just a hormone. We separate controlled human trials, limited human data, animal studies and lab studies, in that order. FDA approval is shown separately. If a peptide’s best evidence is a hormone marker, we say so.

Does raising growth hormone build muscle?

Not by itself, and the studies we found did not test it.

A 2026 scoping review of six peptides, including CJC-1295, ipamorelin, BPC-157 and TB-500, concluded that their claimed benefits remain unsubstantiated by current human trials.

Why is “GH went up” not a result?

A marker is not an outcome. Teichman’s trials show that CJC-1295 acts on the hormone system as intended. They do not show that the change made anyone stronger, leaner or faster. For a muscle-growth claim, the study would need to measure muscle.

What is FDA-approved, and for what?

• Tesamorelin (Egrifta): approved since 2010 for reducing excess abdominal fat in adults with HIV and lipodystrophy. Its label says it is not indicated for weight loss management and that its long-term cardiovascular safety has not been established. Nothing in what we reviewed supports using it for muscle.
• Sermorelin: it was once approved as Geref, which is no longer marketed. FDA determined in 2013 it was not withdrawn for safety or effectiveness reasons. That says nothing about muscle or anti-aging, and a compounded product today is not an approved product. We do not state here whether sermorelin can legally be compounded.
• CJC-1295 and ipamorelin: neither is FDA-approved.

Did the Oct. 30, 2026 HHS policy cover these peptides?

HHS published an interim enforcement discretion policy for six peptides. CJC-1295, ipamorelin, sermorelin and tesamorelin are not among them. BPC-157 and TB-500 are covered, under conditions, and that is not an approval.

For CJC-1295 and ipamorelin specifically:

• FDA’s advisory committee voted against adding either to the compounding list in 2024 (ipamorelin, CJC-1295).
• Both left FDA’s “Category 2” (substances that may present significant safety risks) on April 22, 2026 because the nominations were withdrawn. That did not move them to a permitted category. Ipamorelin remains in Category 2 for 503B outsourcing facilities (FDA).
• We found no federal enforcement discretion that names them. Websites claiming they were “reinstated” do not match FDA’s lists.

FDA evaluated “CJC-1295” and “CJC-1295 DAC” as separate substances. Data on one form should not be assumed for the other.

What are the risks?

• CJC-1295: FDA identified serious adverse events, including increased heart rate and a systemic vasodilatory reaction; limited clinical data; and a potential for immune reactions (FDA).
• Ipamorelin: FDA says a published study identified serious adverse events, including death, when ipamorelin was given intravenously for gastric motility, and that safety information is missing for certain other injection routes. FDA’s page does not name the study, but FDA’s October 2024 briefing document identifies it as Beck 2014, an intravenous trial after bowel surgery, whose authors describe the drug as well tolerated. According to FDA, two people in the ipamorelin group died after bowel resection for colon cancer and an anastomotic leak; FDA says it is unclear whether the deaths were related to the drug, but together with more low potassium and high blood sugar in that group, it raised concern. We report both readings and do not say the drug caused the deaths.
• The whole class: raising growth hormone and IGF-I in people without a deficiency has no established long-term safety record with these products. For context only, the label of tesamorelin, a different drug, warns of neoplasm risk, elevated IGF-1, fluid retention and glucose intolerance. Those are tesamorelin’s label warnings, not findings about the other peptides.
• Gray-market products: HHS describes research-use-only peptides supplied by foreign manufacturers as a safety risk. We do not link to or recommend sellers.

Are these peptides allowed in sport?

No. WADA prohibits growth-hormone-releasing hormones and analogs (CJC-1295, sermorelin, tesamorelin) and growth hormone secretagogues (ipamorelin) in class S2, TB-500 in S2, and BPC-157 at all times in class S0 (2026 list). Athletes should check with their anti-doping organization before taking anything.

Which claims are not supported?

• “The CJC-1295 and ipamorelin stack builds muscle and burns fat.” No published trial of the combination; no muscle or fat outcome in the studies of each.
• “More GH means better results.” A marker is not a result.
• “They were reinstated and are now legal.” Not according to FDA’s lists.
• “Ipamorelin is selective, so it is safe.” FDA says safety information is lacking.
• “Tesamorelin is a fat-burner for anyone.” Approved only for HIV-related abdominal fat.
• “Sermorelin reverses aging.” No randomized trial supports that.

What should you ask a clinician?

• What is my goal, and is there a medical reason (such as a diagnosed hormone deficiency) to test for?
• What does the evidence say about training, nutrition and sleep for my goal, and what is the evidence for any medicine suggested?
• Is the product FDA-approved, and if compounded, who makes it?
• Do I compete in a tested sport?

We do not give doses, cycles or preparation instructions for any of these peptides.

Frequently asked questions

What is the best peptide for muscle growth?

On current evidence, none can be called proven. The best-supported peptide in this family is tesamorelin, which is approved only for abdominal fat in HIV-related lipodystrophy.

Does CJC-1295 with ipamorelin build muscle?

We found no published trial of the combination, and the studies of each measured other things.

Is sermorelin FDA-approved?

It was approved as Geref, which is no longer marketed. A compounded sermorelin product is not an approved drug.

Can athletes use these peptides?

No. They are prohibited by WADA.

How did we rank them?

We rank by the type of evidence first, then its quality and its result. If no peptide has good evidence for a goal, we say so.

1. Human trialsControlled trials in people, published in a journal, that tested a clinical outcome and showed a benefit. The strongest kind of evidence we report.
2. Limited human dataSmall, short or inconclusive human studies, including observational studies, uncontrolled trials and controlled trials that did not show a clinical benefit.
3. Animal studiesResults in animals often don’t carry over to people.
4. Lab studiesCells or tissue in a dish. An early signal, not an answer.

Related guides

• Best Peptides for Weight Loss: What the Evidence Shows
• Best Peptides for Injury Recovery: Human Evidence
• Peptide Glossary: Plain-English Definitions
• How We Rate Peptides: What “Best” Means

Sources we checked

1. CJC-1295 trials in healthy adults, Teichman 2006 (PubMed)PubMed. Accessed October 30, 2026.
2. FDA briefing document on ipamorelin (Oct. 2024)FDA. Accessed October 30, 2026.
3. Ipamorelin in postoperative ileus, Beck 2014 (PubMed)PubMed. Accessed October 30, 2026.
4. FDA: bulk drug substances that may present significant safety risksFDA. Accessed October 30, 2026.
5. FDA advisory committee minutes, Oct. 29, 2024 (ipamorelin)FDA. Accessed October 30, 2026.
6. FDA advisory committee minutes, Dec. 4, 2024 (CJC-1295)FDA. Accessed October 30, 2026.
7. Federal Register: HHS enforcement discretion policy on 503A peptide compounding (Oct. 30, 2026)Other. Accessed October 30, 2026.
8. Peptide Supplements and Their Therapeutic Applications in Sports Medicine, Am J Sports Med 2026 (PubMed)PubMed. Accessed October 30, 2026.
9. Vittone 1997, sermorelin in older men (PubMed)PubMed. Accessed October 30, 2026.
10. FDA determination on Geref (Federal Register, 2013)Other. Accessed October 30, 2026.
11. Egrifta WR prescribing information (DailyMed, rev. 03/2025)FDA. Accessed October 30, 2026.
12. Tesamorelin pooled phase 3 trials, Falutz 2010 (PubMed)PubMed. Accessed October 30, 2026.
13. FDA presentations to the Pharmacy Compounding Advisory Committee (July 23, 2026)FDA. Accessed October 30, 2026.
14. WADA 2026 Prohibited ListOther. Accessed October 30, 2026.

Written and maintained by the Best Peptides For Editorial Team. How we rate evidence.