Mk-677 and Metformin: Can You Take Them Together?

Moderate — Timing Mattersconflict
Evidence-gradedLast reviewed August 8, 2026Source: Nass R, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med (2008);149(9):601-11. PMID 18981485. Supporting: Dichtel LE, et al. J Endocr Soc (2025), PMC12543859; Svensson J, et al. J Clin Endocrinol Metab (1998), PMID 9467542.
Learn about each ingredient:Mk-677Metformin

Quick answer

MK-677 raises growth hormone, and growth hormone reduces the body's sensitivity to insulin. Across multiple controlled trials this shows up as rising fasting blood sugar and rising HbA1c. In a two-year randomised trial, sixteen of forty-three participants taking MK-677 crossed into the impaired fasting glucose range, against two of twenty-two on placebo, and insulin sensitivity fell measurably. A more recent six-month trial saw HbA1c rise significantly, with two of thirteen participants stopping because of high blood sugar. This works directly against what metformin is prescribed to do.

Tell your prescriber you are taking MK-677 if you are on metformin or any diabetes medication, and expect closer blood sugar monitoring. Worth knowing: every trial that measured this excluded people with diabetes at enrolment, so the published data describes what happens to people who started with normal blood sugar. One important practical detail — fasting glucose alone can look normal while a glucose tolerance test is already abnormal.

What happens when you take MK-677 with metformin?

MK-677, also sold as ibutamoren, works by raising growth hormone. One of growth hormone's well-established effects is to make the body less sensitive to insulin, which pushes blood sugar up.

That is the opposite of what metformin is prescribed to do.

Why this matters

This is the best-documented effect of MK-677 in humans, and it has been reproduced across several controlled trials in different populations.

In a two-year randomised trial in older adults, sixteen of forty-three participants taking MK-677 crossed into the impaired fasting glucose range, compared with two of twenty-two on placebo. HbA1c rose while it fell slightly on placebo, and a standard measure of insulin sensitivity declined.

A more recent six-month trial found HbA1c rising significantly against placebo, and two of thirteen participants discontinued because of high blood sugar.

The effect appears dose-related and it reverses when the dose is reduced — in the two-year trial, participants whose glucose rose were managed by cutting the dose.

An important limitation, and why it argues for caution rather than against it

Every trial that measured this excluded people with diabetes at enrolment. So the published data describes what happens to people who started with normal blood sugar. Nothing has been formally studied in people already taking metformin.

That is an absence of data about the higher-risk group, not evidence they are unaffected.

A monitoring detail worth knowing

In one trial, fasting glucose and fasting insulin looked normal while a glucose tolerance test was already abnormal at both two and eight weeks. If monitoring relies on fasting numbers alone, it can miss this.

What to do

Tell your prescriber you are taking MK-677 if you take metformin or any other medication for blood sugar, and expect closer monitoring.

MK-677 is not an approved medicine anywhere and is not a lawful dietary supplement ingredient. It is also flagged by the FDA over a separate safety signal: a trial in patients recovering from hip fracture was stopped early because of a possible signal for heart failure.

This is general information, not medical advice. Do not stop or change a prescribed medicine on your own.

Other Mk-677 interactions

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Other Metformin interactions

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+ alcoholhigh+ vitamin b12high+ psylliummoderate+ glucomannanmoderate+ high-fiber foodslow+ alpha-lipoic acidlow

References

Primary evidence for this article. Always consult your healthcare provider for personal medical advice.

Nass R, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med (2008);149(9):601-11. PMID 18981485. Supporting: Dichtel LE, et al. J Endocr Soc (2025), PMC12543859; Svensson J, et al. J Clin Endocrinol Metab (1998), PMID 9467542. ↗

Reviewed August 8, 2026. How we grade evidence →

Related Topics

mk-677ibutamorenmetformingrowth hormoneinsulin resistanceblood sugarhba1c

Related Interactions

Other interactions you should know about

Mk-677 + Insulin

high

MK-677 raises growth hormone, and growth hormone reduces the body's sensitivity to insulin. Across multiple controlled trials this shows up as rising fasting blood sugar and rising HbA1c. In a two-year randomised trial, sixteen of forty-three participants taking MK-677 crossed into the impaired fasting glucose range, against two of twenty-two on placebo, and insulin sensitivity fell measurably. A more recent six-month trial saw HbA1c rise significantly, with two of thirteen participants stopping because of high blood sugar. This works directly against what insulin is prescribed to do.

Smoking + Insulin

high

Smoking worsens insulin resistance through nicotine-driven catecholamine release, oxidative stress, and inflammation, and slows subcutaneous insulin absorption through vasoconstriction, so people with diabetes who smoke typically need more insulin to reach the same glucose control. Quitting improves insulin sensitivity within days to weeks, so insulin doses often need to come down to avoid hypoglycemia.

Ginger Tea + Metformin

synergy

Ginger (Zingiber officinale) has modest blood-glucose-lowering activity in randomized trials in type 2 diabetes, mainly improving fasting glucose and HbA1c. Combined with metformin the effect is generally additive rather than dangerous. Metformin alone rarely causes hypoglycemia, so the practical concern is small; the risk of a true low rises mainly when ginger is layered onto insulin or an insulin-secreting drug.

Metformin + Alpha-Lipoic Acid

low

Metformin and alpha-lipoic acid both lower blood glucose by independent routes, so their effects can be additive. The added effect is mild for most people, but matters more in those also taking insulin or a sulfonylurea, or who are elderly, thin, or on a beta-blocker.

Metformin + Chromium

low

Chromium is sometimes taken to support blood sugar, and in theory it could add to metformin's glucose-lowering effect. In practice, human trials are mixed: some show a small improvement in insulin sensitivity while most show little or no change in actual blood glucose. The combination is generally well tolerated, but because both are aimed at the same goal, it is worth flagging to your prescriber and watching for any signs of a low.

Metformin + Cinnamon

low

Cinnamon has a mild glucose-lowering effect that can add modestly to metformin's. In pooled human trial data the effect on fasting glucose is small and there are no reports of serious low blood sugar from the combination, so the practical concern is minor for most people. The main extra consideration is choosing the lower-coumarin Ceylon variety for long-term daily supplement use.

Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider before making changes to your supplement or medication routine. Pilora does not diagnose, treat, cure, or prevent any disease.

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