Peptide Profile
MK-677 (Ibutamoren)
The oral growth hormone secretagogue that tricks your body into producing more GH — no needles required.
Dose Range
10-25mg
Frequency
Once daily
Route
Oral (capsule or liquid)
Cycle Length
8-12 weeks
Onset
Moderate (1-2 weeks)
Evidence
Moderate
Compound Profile
Scientific & Efficacy Data
C27H36N4O5S
Molecular Formula
528.7 g/mol
Molecular Weight
4-6 hours (IGF-1 elevation persists ~24 hours)
Half-Life
High oral bioavailability
Bioavailability
159634-47-6
CAS #
178024
PubChem ID ↗
Developed By · 1995
Merck Research Laboratories
Merck & Co.
Primary Benefits
MK-677 effectively builds lean muscle mass and improves body composition in clinical trials. Users gain 1-2 kg of lean mass over 8-12 weeks while losing fat, making it excellent for recomposition goals.
Growth hormone elevation significantly accelerates muscle recovery, reduces soreness, and improves athletic performance. These benefits compound over weeks, making training more sustainable.
MK-677 deepens sleep architecture and enhances sleep quality, supporting better recovery and metabolic function. Improvements in insulin sensitivity, LDL cholesterol, and overall energy are documented in clinical research.
Amino Acid Sequence
N/A — Non-peptide small molecule (spiroindoline growth hormone secretagogue)Dosing
How much
do I take?
Timing
Best time to take
Morning (helps with daytime GH elevation) or early evening (does not significantly disrupt sleep despite oral bioavailability)
With food?
Can be taken with or without food. Food may slightly slow absorption but does not meaningfully reduce effectiveness.
If stacking
Once-daily dosing makes it easy to stack with other compounds. Take alongside morning protein and micronutrients for optimal recovery support.
Adjusting Your Dose
Increase if
- +Tolerating 10 mg well after 3 weeks with minimal side effects
- +Not seeing IGF-1 elevation after 2-3 weeks at current dose
- +Comfortable appetite increase and no metabolic concerns
Decrease if
- -Severe increased appetite affecting eating patterns or energy
- -Joint pain, carpal tunnel, or fluid retention becomes bothersome
- -Fasting glucose elevates significantly (> 20 mg/dL above baseline)
Signs of right dose
- ✓Energy and strength gains visible in 4-6 weeks
- ✓Improved sleep quality and recovery
- ✓Measurable increase in lean mass without excess fat gain
Dosing Calculator
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Suitability
Is this
right for me?
Best For
Older Adults (60+) Seeking Body Composition Improvements
MK-677 was designed for aging populations. It restores GH and IGF-1 to youthful levels, increases lean mass, and improves physical function in people over 60. A 2-year clinical trial showed a 1.1 kg gain in fat-free mass with only modest fat gain—ideal for maintaining strength in older age.
Athletes and Fitness Enthusiasts Wanting Recovery Support
Oral dosing makes MK-677 convenient for athletes. It enhances muscle protein synthesis, speeds recovery after intense training, and supports lean mass building without the hassle of injections.
People with Chronic Wasting or Protein Deficiency
Clinical trials show MK-677 helps treat protein-energy wasting in kidney disease and other conditions. It stimulates appetite (a feature in these populations) and preserves muscle tissue—making it useful for those losing mass despite good nutrition.
Consider Alternatives If
Who Should Avoid
Do not use if
- ×You have uncontrolled diabetes or severe metabolic dysfunction
- ×You are pregnant, breastfeeding, or planning pregnancy
- ×You have active cancer or are undergoing cancer treatment
- ×You have a severe allergy to any component of the formulation
- ×You are taking high-dose insulin without medical supervision
- ×You have severe carpal tunnel syndrome or joint disease
Use with caution if
- !You have a family history of diabetes (monitor fasting glucose closely)
- !You are predisposed to elevated blood pressure
- !You have mild sleep apnea (may worsen slightly with use)
- !You are taking thyroid medication (may require dose adjustment)
- !You have mild arthritis or joint pain (may worsen transiently)
- !You are overweight or have metabolic syndrome (increased appetite risk)
Administration
How do I
use it?
Injection
Route
Oral administration — no injection required. Simply swallow the capsule with water or measure the liquid dose with a dropper.
Best sites
- •N/A — taken by mouth
Technique
- 1.Step 1: Take one MK-677 capsule or measure the liquid dose (typically 1 mL for 25 mg) in the morning or early evening.
- 2.Step 2: Swallow with a full glass of water. No need to chew or open the capsule.
- 3.Step 3: Can be taken with or without food—choose what works best for your routine.
- 4.Step 4: Maintain consistent timing (same time each day) to optimize GH secretion patterns.
- 5.Step 5: No need for post-injection care, site rotation, or sterile technique—one of the major advantages of oral MK-677.
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
MK-677 has been studied in hundreds of humans over 2+ years and is generally well tolerated. Most side effects are mild and manageable, especially with lower starting doses. The lack of injection requirement makes it safer than injectable GH in terms of infection risk and sterility concerns. However, it is not FDA approved and should be viewed as a research compound.
Clinical evidence comes from Phase 1-2 trials in healthy older adults, Alzheimer's patients, and kidney disease patients. Long-term safety is supported by 2-year data. No Phase 3 pivotal trials have been completed, limiting approval pathway.
Common Side Effects
Experienced by some users
Increased appetite
Most users experience heightened hunger within the first 1-2 weeks. Appetite typically normalizes after 4-6 weeks as the body adapts. This occurs because MK-677 stimulates ghrelin signaling.
Management: Eat protein-rich meals to feel fuller longer. Stay hydrated. Consider taking MK-677 in the morning to manage hunger throughout the day. This side effect can be leveraged if you're trying to gain muscle.
Mild water retention or edema
Slight puffiness in hands, feet, or face may appear in weeks 2-4. This is usually mild and resolves with continued use. Related to increased IGF-1 and growth signaling.
Management: Increase potassium intake (bananas, sweet potatoes). Reduce sodium if bloating is bothersome. Compression socks may help with ankle swelling. Mild edema is not dangerous but can be uncomfortable.
Elevated fasting glucose
Fasting blood sugar may increase by 5-15 mg/dL, reflecting mild insulin resistance that typically develops with GH elevation. This is reversible and usually mild in healthy individuals.
Management: Monitor fasting glucose every 4 weeks. Maintain regular exercise and limit refined carbohydrates. If glucose rises > 30 mg/dL or exceeds 130 mg/dL, discontinue and consult a doctor.
Less Common
- •Joint or muscle pain
- •Carpal tunnel syndrome or nerve compression symptoms
- •Mild nausea or digestive upset
These typically resolve with continued use or dose adjustment.
Stop and Seek Help If
- ×Fasting glucose becomes elevated and uncontrollable (> 130 mg/dL despite diet changes)
- ×Severe allergic reaction such as itching, swelling, or breathing difficulty
- ×Joint pain or carpal tunnel symptoms worsen and persist beyond 3 weeks
- ×Blood pressure elevation becomes problematic (systolic > 150 mmHg)
- ×Suspicion of liver or kidney dysfunction (yellowing of skin, dark urine)
- ×Planned surgery or medical procedure (discontinue 2 weeks before)
This list is for informational purposes and does not replace medical advice. Stop use and consult a healthcare provider immediately if you experience any concerning symptoms. Individual responses vary, and a doctor can help determine if MK-677 is appropriate for your health profile.
Interactions
With other peptides
- ✓Synergistic effect — both stimulate GH release. Stacking may amplify GH and IGF-1 elevation but increases side effect risk.
- ✓Complementary anabolic effects. MK-677 enhances protein synthesis; testosterone boosts muscle growth. Combination is effective but requires monitoring.
With medications
- !Insulin or insulin secretagogues (metformin, sulfonylureas) - Risk of hypoglycemia. MK-677 raises blood glucose; combining with insulin-lowering drugs can cause dangerously low blood sugar.
- ✓Thyroid medications (levothyroxine) - MK-677 may increase metabolic rate slightly. Thyroid dose may need adjustment. Monitor TSH every 4-6 weeks.
- ✓Blood pressure medications - MK-677 may mildly elevate blood pressure. ACE inhibitors or ARBs may need dose adjustment. Monitor BP regularly.
- ✓Estrogen or hormonal birth control - Theoretical risk of interaction via hormone signaling. Use with medical supervision if taking hormonal medications.
With supplements
- ✓Creatine monohydrate - Synergistic for muscle gains. No safety concerns. Combination is common among athletes.
- ✓Whey protein or BCAAs - Complementary for muscle protein synthesis. MK-677 boosts anabolism; protein provides building blocks. Safe and synergistic.
- ✓Melatonin or sleep supplements - MK-677 enhances sleep; melatonin adds to this. Safe combination for better recovery. No contraindications.
Effectiveness
Does it
work?
Evidence Level
Moderate human trials
What to Expect
Week 1-2
What you might notice
- •Increased appetite (the most common early sign)
- •Slightly better sleep quality
- •Mild energy boost or fatigue (varies)
What's normal
- •Appetite increase is expected and normal — it means MK-677 is working
- •Mild water retention may start appearing
- •No dramatic changes in strength or body composition yet
What's next
- →Blood tests will show elevated IGF-1 levels (confirm efficacy)
- →GH pulses increase but remain below peak levels
- →Continue consistent dosing; effects compound over weeks
Week 3-4
What you might notice
- •Improved recovery after workouts
- •Appetite normalizing or becoming manageable
- •More defined muscle pumps during training
- •Noticeably better sleep architecture
What's normal
- •Joint aches may appear (growth signaling outpacing adaptation)
- •Mild carpal tunnel symptoms in some users
- •Slight increase in body weight (mostly water and muscle)
What's next
- →Switch from starting dose to standard dose if tolerating well
- →Body composition changes begin (lean mass > fat gain)
- →Second blood test often shows stronger IGF-1 elevation
Week 5-8
What you might notice
- •Visible increase in muscle definition and fullness
- •Reduced body fat percentage (if diet is dialed in)
- •Measurable strength gains in major lifts
- •Improved athletic performance and endurance
- •Consistently better sleep and mood
What's normal
- •Fasting glucose may be elevated but typically mild
- •Joint pain usually resolves by now
- •Water retention stabilizes at a low level
- •Appetite levels out to a new baseline
What's next
- →Peak IGF-1 elevation is established
- →Continued lean mass gains and fat loss acceleration
- →Third blood test confirms sustained elevation
Week 9-12
What you might notice
- •Marked improvements in body composition
- •Peak muscle hardness and vascularity
- •Strength levels at or near cycle peak
- •Excellent recovery even from high training volume
- •Stable, elevated baseline energy
What's normal
- •Side effects remain minimal or absent
- •Fasting glucose plateau (important to monitor)
- •Body adapted to appetite stimulation
- •Sleep quality remains enhanced
What's next
- →Consider cycle completion or continuation based on goals
- →If extending cycle, take a 4-6 week break before restarting
- →Final blood work confirms efficacy and safety profile
Signs It's Working
Laboratory markers
- ✓Serum IGF-1 elevation of 50-100% above baseline (measured via blood test)
- ✓Growth hormone pulse frequency and amplitude increase on 24-hour GH testing
- ✓Fasting glucose modest increase (typically 5-15 mg/dL, reversible)
Physical and performance improvements
- ✓Lean muscle mass gain of 1-2 kg over 8-12 weeks
- ✓Measurable strength increases in major lifts (5-15% improvement)
- ✓Improved muscle recovery and reduced soreness after training
- ✓Body fat loss or body recomposition favoring muscle over fat
Quality of life markers
- ✓Improved sleep quality and deeper restorative sleep
- ✓Increased energy and overall sense of well-being
- ✓Enhanced appetite (useful for those needing to gain mass)
- ✓Improved mood and cognitive function
Not Seeing Results?
Common reasons
- •Dose too low: Starting at 10 mg may show muted results. If no improvements by week 4, consider increasing to 25 mg.
- •Inconsistent timing: Varying dose times by hours disrupts GH pulse patterns. Lock in a consistent daily time to maximize effect.
- •Poor diet or inadequate protein: MK-677 boosts growth signals, but muscle synthesis requires protein. Ensure 1-1.2g protein per pound of body weight.
- •Insufficient sleep: MK-677 enhances sleep, but you must provide adequate sleep duration (7-9 hours). Poor sleep blunts gains.
- •High stress or cortisol: Stress hormone cortisol opposes growth signaling. Manage stress with exercise, meditation, or other techniques.
- •Underlying metabolic issues: Uncontrolled diabetes, thyroid dysfunction, or severe metabolic syndrome can blunt MK-677 effectiveness. Get bloodwork done.
Key Research
"Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial"
Nass R, et al., 2008
Finding: In a 2-year randomized controlled trial with 65 healthy adults aged 60-81, MK-677 at 25 mg daily significantly raised growth hormone and IGF-1 to youthful levels. The treatment group gained 1.1 kg of fat-free mass compared to a 0.5 kg loss in the placebo group (p < 0.001). Body weight increased by about 2.7 kg overall. The most common side effects were increased appetite (which improved after several months), mild swelling, and mild muscle pain. Fasting glucose increased slightly, while LDL cholesterol decreased. The compound was well tolerated over the full 2 years.
View Study"Oral ghrelin receptor agonist MK-0677 increases serum IGF-1 in hemodialysis patients"
Campbell GA, et al., 2018
Finding: In a crossover randomized controlled trial of 22 hemodialysis patients, MK-0677 produced a 65 percent greater increase in IGF-1 compared to placebo (p < 0.001). No serious adverse effects were observed. This research demonstrates promise for treating protein-energy wasting in patients with kidney disease—a condition where muscle loss threatens quality of life.
View Study"Growth hormone secretagogue MK-677: no clinical effect on AD progression in a randomized trial"
Sevigny JJ, et al., 2008
Finding: In a Phase 2 randomized controlled trial with 512 Alzheimer's disease patients, MK-677 raised IGF-1 levels as expected but did not slow cognitive decline or disease progression compared to placebo. The compound was well tolerated with no safety concerns. Although it successfully elevated IGF-1, raising this hormone alone was not sufficient to treat Alzheimer's pathology.
View Study"MK0677, a Ghrelin Mimetic, Improves Neurogenesis but Fails to Prevent Hippocampal Lesions in a Mouse Model of Alzheimer's Disease"
Tian J, et al., 2019
Finding: In mouse models of Alzheimer's disease, MK-677 successfully improved neurogenesis—the growth of new brain cells—but could not prevent hippocampal damage and neuronal loss caused by Alzheimer's pathology. This suggests MK-677 activates growth and repair mechanisms but cannot overcome the fundamental disease process.
View StudyFrequently Asked Questions