Hepatotoxicity induced by MK-677. — VialBase Research

Summary

MK-677, a growth hormone secretagogue, is gaining popularity among performance-enhancing supplements. Its recognised side effects include oedema, increased appetite and muscle pain, while reports of hepatotoxicity are scarce. This case report documents one: an otherwise healthy man in his early 30s who developed transaminitis — elevated liver transaminases, the biochemical marker of hepatocellular injury — after consuming MK-677 for 2 months before presentation. His liver function tests eventually returned to normal limits after he stopped the supplement. The report is short, and its value is exactly its specificity: this was not an elderly or comorbid patient, not a supratherapeutic exposure over years, and not a case confounded by an underlying liver condition. It was a healthy man in his 30s, two months of use, and measurable liver injury that resolved on withdrawal. Because published hepatotoxicity reports for MK-677 are scarce, this case establishes liver injury as a documented outcome of use rather than a theoretical concern.

Key Findings

• An otherwise healthy man in his early 30s developed transaminitis after consuming MK-677 for 2 months before presentation
• Liver function tests eventually returned to normal limits after stopping the supplement, consistent with a drug-related injury that resolved on dechallenge
• The exposure was short: two months of use was sufficient for measurable hepatic injury in a previously healthy person
• MK-677’s more commonly recognised side effects are oedema, increased appetite and muscle pain — liver injury is not among the effects users are typically warned about
• Reports of hepatotoxicity with MK-677 are scarce in the literature, so this case adds a documented instance to a very thin safety record

Relevance to MK-677

This is the most important safety document in the MK-677 set and it should not be hedged. A healthy man in his early 30s — the demographic that buys this compound — developed liver injury after two months of use, and his liver enzymes normalised only after he stopped. MK-677 is not an approved medicine; it is sold as a performance-enhancing supplement, which means there is no prescriber monitoring liver function, no label warning to prompt testing, and no adverse-event reporting system that would surface cases like this systematically. The scarcity of published hepatotoxicity reports should therefore not be read as evidence of hepatic safety — an unmonitored, unapproved product used outside medical supervision generates almost no case literature regardless of how often harm occurs. As a single case report this cannot establish incidence, and that limitation is real. What it does establish is that the harm is possible, that it can occur in a healthy young user within two months, and that anyone using MK-677 has a concrete reason to have liver function checked and to stop if transaminases rise.

Citation

Cobani E, Amin MS, Hasso M, et al. Hepatotoxicity induced by MK-677. BMJ case reports. 2025;18(7). doi:10.1136/bcr-2025-265728.

See Also

• Parent compound: MK-677