MK-677 Height Growth: Can MK-677 Increase Height?

Can MK-677 increase height? There is no evidence that it makes healthy teenagers or adults taller. It has only been tested for height in young children with diagnosed growth hormone deficiency, treated by specialists, and even there it worked less well than growth hormone injections. No trial has tested it in healthy 16-, 17- or 18-year-olds, and once your growth plates close, no drug can make your bones longer.

People ask this because MK-677 raises growth hormone (GH). Below is what the studies actually show, what happens to growth plates, how MK-677 compares with GH injections, and the risks for teenagers. For the compound itself, see our MK-677 (ibutamoren) review.

MK-677 – short summary

MK-677 (ibutamoren) is an oral drug that copies the hormone ghrelin and makes the pituitary release more GH, which raises IGF-1 (FDA 2024). It is not approved as a medicine anywhere we could find; as LUM-201 it is in a Phase 3 trial for children with GH deficiency (NCT06948214). Its common side effects in trials were increased appetite, swelling, muscle pain and higher blood sugar (Nass 2008). More in MK-677 side effects.

Can MK-677 increase height?

Only in one group has it been shown to speed up growth: prepubertal children with diagnosed GH deficiency. In that group, growth speeded up compared with placebo, but less than with standard GH injections:

Those children were picked carefully: they had a delayed bone age, low GH on two standard tests, and had to respond to a single test dose before they could join (FDA 2024). The FDA concluded that height results in these trials “suggest inferior efficacy compared to approved therapies” (FDA 2024).

No trial has given MK-677 to healthy children, healthy teenagers or adults to see whether they grow taller. A search of PubMed for ibutamoren and height (30 October 2026) found only studies in GH deficiency and reviews.

Who can still increase their height?

Bones grow longer at the growth plates near the ends of the long bones. Once growth is complete, “sometime during adolescence”, the growth plates close and are replaced by solid bone; girls’ bones finish growing sooner than boys’ (NIAMS). After that, nothing taken by mouth can lengthen them.

If you are 16 or 17 and your plates are still open, you are still growing anyway. That is exactly why no one can tell, from an individual story, whether MK-677 added anything. Some children grow slowly because of a real medical problem, and very slow growth can be a sign of a gland problem that doctors can treat (MedlinePlus). If height worries you, a doctor can check whether you are still growing and why.

What do the studies say?

• Short-term hormone studies: in 18 GH-deficient children, 7–8 days of ibutamoren raised GH, IGF-1 and IGFBP-3 in some of them (Codner 2001).
• Six-month growth trials: faster growth than placebo but slower than GH injections, in carefully selected GH-deficient children (table above).
• Phase 3: a 12-month placebo-controlled trial of LUM-201 in children with GH deficiency has been recruiting since May 2026 (NCT06948214).

A correction: an older version of this page said a study “tested individuals over a period of a year”, that everyone under 18 grew at least 3 cm and that the group took 12.5 mg daily. The study it linked (Chapman 1997) gave 10 or 50 mg to nine GH-deficient men aged 17 to 34 for four days per period and measured hormones, not height. Those claims were wrong and have been removed.

People who say they grew taller with MK-677

The earlier version of this page described two users from a limb-lengthening forum: one who went from 5’4″ to about 5’7″ between ages 17 and 19, and one who went from 5’6″ to 6’2″ between 15 and 18. Stories like these can’t show that MK-677 did anything, because teenagers grow during exactly those years anyway, and there is no way to know how tall they would have been without it. We have removed the doses they reported, since no study supports any dose for healthy teenagers.

How much taller can you grow with MK-677?

For healthy teens and adults: unknown, because it has never been measured. The only numbers are from GH-deficient children, who grew 6.0 to 8.2 cm a year on ibutamoren vs 10.6 to 11.1 cm on GH injections over six months (FDA 2024, NCT04614337). Those children were small for their age because they lacked GH; a teenager with normal GH is in a completely different situation. The older claim on this page of “5–10 cm (2–3 inches) a year” for anyone with open growth plates had no study behind it.

MK-677 vs GH shots for increasing height

Sources: FDA 2024, NCT04614337. In the US, distributing GH for any use other than an authorized medical treatment on a doctor’s order is a federal crime, with higher penalties when someone under 18 is involved (21 U.S.C. § 333(e)). More comparisons in MK-677 vs HGH.

MK-677 height increase after puberty

Once your growth plates have closed, MK-677 cannot make you taller, and neither can growth hormone (NIAMS). The only trials showing faster growth were in prepubertal children with GH deficiency (FDA 2024).

Risks for teenagers

• No safety data in healthy teens. Every MK-677 trial in young people was in children with GH deficiency under specialist care (FDA 2024).
• GH-related risks in growing bones. Approved GH medicines warn about slipped capital femoral epiphysis (a hip growth-plate problem) and worsening scoliosis in children, plus raised blood sugar and fluid retention; the FDA says similar risks may apply to ibutamoren (FDA 2024).
• Blood sugar. MK-677 raised fasting glucose and HbA1c in adult trials (Nass 2008).
• Sport. MK-677 is banned at all times by WADA, for any athlete tested under anti-doping rules (WADA 2026).
• Product quality. Products sold online often don’t match their labels (Van Wagoner 2017).

Conclusion

MK-677 has been shown to speed up growth only in young children with diagnosed GH deficiency, and less than GH injections do. There is no study showing it makes healthy 16-, 17- or 18-year-olds taller, and after the growth plates close it can’t. If you are worried about your height, the useful step is seeing a doctor who can check whether you are still growing and whether anything is holding you back.