Side by side
Hexarelin vs MK-677
Both are discussed for muscle & performance and anti-aging & longevity. What this site records about each, side by side. Every figure is on the compound's own page with the source it came from.
| Hexarelin | MK-677 | |
|---|---|---|
| What it is | The most potent growth hormone releasing peptide of the three, and the only one that reliably stops working. Its response fades within about two weeks of continuous use. | An orally active ghrelin receptor agonist that raises growth hormone and IGF-1. Not a peptide, and not injected. It is a small molecule taken by mouth. |
| EvidenceHow much human evidence exists, not how well it works. | Early human trials | Early human trials |
| Regulatory statusReviewed 2026-08-16 | Not approved for human use in any jurisdiction. Reached early-phase clinical study in the 1990s; development did not continue, in part because the growth hormone response was not sustained. Sold only as a research chemical. | Not approved for human use in any jurisdiction. Development was not completed. It is widely sold as a 'research chemical' or mislabelled as a dietary supplement, which it is not. It is an unapproved drug. |
| Routes | Subcutaneous | Oral |
| Half-life | 0.9 hours | 24 hours |
| Cheapest per mgVials only, read from vendors' own listings and dated on the price index. | $5.91/mg | $0.64/mg |
| Median per mg | $8.82/mg | $2.94/mg |
| Vendors with a price | 17 | 6 |
| Storage once mixed | Refrigerated at 2–8 °C. Do not freeze once mixed. | Not applicable. Liquid preparations sold in solution should follow the seller's storage instructions, which is a weaker guarantee than it sounds. |
Compare two other compounds · The full price index
This page is educational. It describes what published research reports, not what you should do. Peptides discussed here are largely not approved for human use, and nothing on BioAlmanac is medical advice. Nothing here ranks these two against each other. A table can show that one has more human evidence behind it or costs less per milligram; neither of those is a recommendation, and the right comparison for any person is one their doctor makes with them.