Seven Days of Oral MK-677 Boosts 24-Hour Growth Hormone Profiles in Young Men
Seven days of bedtime oral MK-677 at 25 mg significantly increased 24-hour GH profiles and IGF-1 levels in healthy young men without disrupting cortisol rhythms.
Quick Facts
What This Study Found
Bedtime MK-677 at 25 mg for 7 days significantly increased 24-hour GH profiles and IGF-1 in young men without altering adrenocortical function.
Key Numbers
How They Did This
Randomized, double-blind, three-period crossover study. 9 healthy young men received placebo, 5 mg, or 25 mg MK-677 orally at bedtime for 7 consecutive days per period. 24-hour GH profiles, IGF-1, and cortisol were measured.
Why This Research Matters
This study established a practical dosing protocol (25 mg at bedtime) for MK-677 and confirmed it works in young men without disrupting the cortisol axis — a key safety consideration.
The Bigger Picture
This study helped establish the standard MK-677 dosing protocol (25 mg at bedtime) that is widely referenced in subsequent research and clinical practice.
What This Study Doesn't Tell Us
Very small sample (9 men). Only 7-day treatment period. No women included. Limited to hormonal endpoints without functional outcome measures.
Questions This Raises
- ?Does the GH-boosting effect of MK-677 persist with longer-term use, or does tolerance develop?
- ?Would women show similar responses to MK-677 at these doses?
Trust & Context
- Key Stat:
- 25 mg effective, 5 mg not The 25 mg bedtime dose significantly increased GH and IGF-1, while 5 mg showed lesser effects
- Evidence Grade:
- Strong study design (randomized, double-blind, crossover) but very small sample size (9). Provides robust individual-level data but limited generalizability.
- Study Age:
- Published in 1996, this is a key early dosing study for MK-677. The 25 mg bedtime protocol it established remains the standard reference dose.
- Original Title:
- Effects of a 7-day treatment with a novel, orally active, growth hormone (GH) secretagogue, MK-677, on 24-hour GH profiles, insulin-like growth factor I, and adrenocortical function in normal young men.
- Published In:
- The Journal of clinical endocrinology and metabolism, 81(8), 2776-82 (1996)
- Authors:
- Copinschi, G(2), Van Onderbergen, A(2), L'Hermite-Balériaux, M, Mendel, C M, Caufriez, A, Leproult, R, Bolognese, J A, De Smet, M, Thorner, M O, Van Cauter, E
- Database ID:
- RPEP-00358
Evidence Hierarchy
Frequently Asked Questions
Why is MK-677 taken at bedtime?
Growth hormone is naturally released in pulses during sleep. Taking MK-677 at bedtime amplifies these natural sleep-associated GH pulses, working with the body's rhythm rather than against it.
Did MK-677 affect cortisol levels?
No. Despite boosting growth hormone, MK-677 did not alter adrenocortical function or cortisol rhythms, which is important because disrupting cortisol could cause significant side effects.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-00358APA
Copinschi, G; Van Onderbergen, A; L'Hermite-Balériaux, M; Mendel, C M; Caufriez, A; Leproult, R; Bolognese, J A; De Smet, M; Thorner, M O; Van Cauter, E. (1996). Effects of a 7-day treatment with a novel, orally active, growth hormone (GH) secretagogue, MK-677, on 24-hour GH profiles, insulin-like growth factor I, and adrenocortical function in normal young men.. The Journal of clinical endocrinology and metabolism, 81(8), 2776-82.
MLA
Copinschi, G, et al. "Effects of a 7-day treatment with a novel, orally active, growth hormone (GH) secretagogue, MK-677, on 24-hour GH profiles, insulin-like growth factor I, and adrenocortical function in normal young men.." The Journal of clinical endocrinology and metabolism, 1996.
RethinkPeptides
RethinkPeptides Research Database. "Effects of a 7-day treatment with a novel, orally active, gr..." RPEP-00358. Retrieved from https://rethinkpeptides.com/research/copinschi-1996-effects-of-a-7day
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.