MK-677 dosage and protocol
Last reviewed Oct 7, 2026. Editorial policy
US regulatory status: FDA Category 2: significant safety risk
Oral growth hormone secretagogue (Ibutamoren). Increases GH and IGF-1 levels without injections.
- Vial size: 25 mg
- Concentration: Oral - 25mg tablets
- Administration: oral
Research areas
- Growth Hormone
- Muscle Growth
- Sleep Quality
- Bone Density
Quick start
- Reconstitute: Not required; oral 25 mg tablets
- Typical dose: Up to 25 mg by mouth once daily, often started lower
- Easy measuring: No syringe needed; one 25 mg tablet per day at the full dose
- Storage: Sealed container, cool and dry, away from moisture
How it works
MK-677 (ibutamoren) is an orally active, non-peptide growth hormone secretagogue. It mimics ghrelin by activating the growth hormone secretagogue receptor (GHS-R1a) in the pituitary and hypothalamus, which amplifies the natural pulses of growth hormone (GH) and, downstream, raises insulin-like growth factor 1 (IGF-1). Because it has a long half-life (roughly 24 hours) and is taken by mouth, a single daily dose can keep GH and IGF-1 elevated around the clock. It also stimulates appetite and can raise cortisol modestly, both consistent with ghrelin receptor activity. In human trials, including studies in healthy older adults lasting up to two years, daily MK-677 increased GH and IGF-1 into the range of younger adults and increased fat-free mass, though gains in strength and function were not clearly shown. Studies also reported changes in sleep architecture, with more deep and REM sleep in small groups. A trial in older adults recovering from hip fracture was stopped early, partly due to a higher rate of congestive heart failure in the treatment group. Consistently, MK-677 raised fasting glucose and reduced insulin sensitivity. It is not approved as a medicine anywhere and is prohibited in sport.
Units chart for a 25 mg vial
| Water added | Strength | 1 unit = | 100 mcg | 250 mcg | 500 mcg |
|---|---|---|---|---|---|
| 1 mL | 25 mg/mL | 250 mcg | 0.4 units | 1 units | 2 units |
| 2 mL | 12.5 mg/mL | 125 mcg | 0.8 units | 2 units | 4 units |
| 3 mL | 8.33 mg/mL | 83.3 mcg | 1.2 units | 3 units | 6 units |
Units on a U-100 insulin syringe (100 units = 1 mL).
Storage
Evidence: Unknown. We found no usable data.
- Powder or unopened: Usually sold as capsules or an oral liquid, not a powder to mix. Follow the product label.
- Mixed or in use: Not reconstituted.
- Use within: no tested number
- Light: Unknown.
Most reconstituted peptides are kept in the refrigerator (2–8 °C) and used within about 28 days. That is a convention, not tested data: the 28 days comes from the USP <797> limit for opened multiple-dose containers, which is about sterility, not about whether the peptide stays intact.