SM-130686
Experimental oral growth hormone secretagogue with anabolic potential from preclinical research
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Typical dose
5–20 mg
Compound profile
Scientific & efficacy data
Growth Hormone
Peptide profile
Moderate human trials
SM-130686
5–20 mg · Multiple times daily
Molecular formula
C22H24Cl2F3N3O3
- Mol. weight
- 506.3 g/mol (as HCl salt)
- CAS number
- 259667-25-9
- PubChem
- 9914145
- Developed · 2001
- Jun Nagamine et al.
Sumitomo Pharmaceuticals Co. Ltd (Discovery Research Laboratories II, Osaka, Japan) — now Dainippon Sumitomo Pharma
Amino acid sequence
N/A — Non-peptide small molecule (oxindole-based growth hormone secretagogue)Muscle and Strength
Preclinical data shows dose-dependent increases in fat-free mass and body weight in rats given 10 mg/kg twice daily. No human data. Potential moderate benefit for lean mass building if human response matches animal models, but benefit is theoretical and unproven. Requires proper training and nutrition to manifest.
Recovery and Performance
GH accelerates tissue repair and collagen synthesis. Rat studies suggest improved training capacity and reduced soreness. Potential benefit for athletic recovery, but magnitude and safety in humans unknown. Evidence is limited to animal models only.
Metabolic Health
GH supports metabolic rate and fat mobilization. Limited evidence in preclinical work suggests possible fat loss potential. High uncertainty regarding human metabolic effects. Antagonism of insulin action may worsen glucose control in some individuals, offsetting benefits.
Dosing
How much do I take?
Covers timing · dose-adjustment guidance.
Suitability
Is this right for me?
Best for lean mass building (theoretical) & strength development (preclinical evidence)
Best for
Lean Mass Building in Trained Athletes
SM-130686 targets GHS-R to stimulate GH release, which supports anabolic processes. Preclinical studies in rats showed significant increases in fat-free mass and body weight when combined with resistance training principles.
Age-Related GH Decline
As a GHS-R agonist, SM-130686 may help restore physiological GH secretion in adults experiencing age-related decline. The oral route is convenient for long-term administration.
Recovery and Performance
GH supports tissue repair, collagen synthesis, and recovery. May benefit individuals engaged in intensive resistance training or athletic performance work.
Consider alternatives if
Do not use if
Use with caution if
Not sure?
Compare SM-130686 with similar peptides to find the best fit for your goals.
Administration
How do I use it?
Oral capsule or powder
Route
Not applicable — oral formulation only
Best sites
Covers reconstitution · step-by-step technique · storage · a sample daily schedule.
Safety
Is it safe?
2 common side effects · 4 serious
SM-130686 is a research compound that has never been tested in humans.
All safety and efficacy data come from animal studies (primarily rats). No human clinical trials have been conducted. Use carries unknown risks. Potential side effects based on GH physiology and limited preclinical work.
PRECLINICAL ONLY — This compound has not entered human clinical trials. No FDA data available. Safety profile in humans is completely unknown. All dosing is extrapolated from rat studies and should not be considered established for human use. This is an experimental research compound.
Common side effects · experienced by some users
Appetite stimulation
GHS-R agonists increase appetite through ghrelin-like action on hypothalamus. May be mild to moderate depending on dose and sensitivity.
Management: Eat planned meals to satisfy appetite. Stay hydrated. If excessive, reduce dose or frequency.
Transient water retention
GH promotes sodium retention and fluid shifts. Usually mild and resolves within days of stopping. Can slightly increase body weight independent of muscle gain.
Management: Maintain normal hydration and electrolyte intake. Reduction is natural when discontinuing. Monitor weight trends over 2-week intervals.
Less common
These typically resolve with continued use or dose adjustment.
Stop and seek help if
- Severe or worsening joint pain (possible early carpal tunnel)
- Uncontrolled blood glucose elevation (especially if diabetic)
- Signs of edema or swelling in hands/feet that doesn't resolve
- Development of numbness or tingling in hands (median nerve compression)
- Severe sleep disturbances or mood changes
- Any signs of allergic reaction (rash, difficulty breathing, swelling)
- Diagnosis of cancer during treatment
- Symptoms suggestive of acromegaly progression (facial coarsening, hand/feet growth)
This is a research compound with no human safety data. Serious side effects are possible and unknown. If any concerning symptoms develop, discontinue immediately and seek medical evaluation. Unknown long-term effects. Do not combine with other GH secretagogues. This is NOT medical advice. Consult a physician before use.
With other peptides
- Caution:
- Caution:
- Caution:
- Caution:
With medications
- Caution:
- Caution:
- Caution:
- Caution:
- Caution:
With supplements
- Safe:
- Safe:
- Safe:
- Safe:
Effectiveness
How do I know it's working?
Moderate human trials · first signs week 1-2
Evidence level
Moderate human trials
(Phase 1-2)
Regulatory status
Research compound
Onset of effects
Moderate
(1-2 weeks)
How it works
SM-130686 is a small pill that tricks your body into making more growth hormone.
Growth hormone builds muscle, burns fat, and helps you recover from exercise. SM-130686 works by activating the ghrelin receptor in your brain, which tells your body to release more of its own natural GH. It's about 55% as strong as ghrelin (your body's natural GH trigger).
The cool part: it's a pill you can swallow, so no needles needed. The catch: we only know it works this way in rats; we don't have human data yet.
The deeper mechanism
SM-130686 is a non-peptide oxindole derivative that functions as a partial agonist at the growth hormone secretagogue receptor (GHS-R, also called ghrelin receptor). GHS-R is a G-protein coupled receptor found primarily in the anterior pituitary gland and hypothalamus.
Upon binding, SM-130686 activates GHS-R signaling, leading to activation of GHRH neurons in the hypothalamus and direct stimulation of GH secretion from somatotroph cells.
The drug achieves approximately 55% intrinsic activity relative to the endogenous agonist ghrelin, classifying it as a partial agonist. This partial agonism may provide a more physiological GH secretion pattern compared to full agonists, though this has not been tested in humans.
The drug is orally bioavailable (28% in rats) due to its small-molecule structure and lipophilicity, allowing it to cross the blood-brain barrier and gut epithelium. Once absorbed, SM-130686 is thought to undergo hepatic metabolism.
In preclinical rat models, SM-130686 dose-dependently stimulates GH release, with peak effects observed at 10 mg/kg (approximately 0.5-1.5 mg/kg in humans for equivalent effect, though exact scaling is uncertain).
Chronic administration leads to elevated circulating IGF-1 levels, indicating sustained GH bioactivity.
The anabolic effects observed in animal studies (increased lean mass, body weight, fat-free mass) are attributed to GH's well-characterized effects on protein synthesis, lipolysis, and metabolic rate.
Notably, SM-130686 binds a distinct but overlapping pocket on GHS-R compared to ghrelin, allowing structural optimization and selectivity. The compound represents a class of non-peptide GHS-R agonists that offer oral administration compared to peptide secretagogues requiring injection.
What to expect
Week 1-2
What you might notice
- Appetite increase (often noticeable within first 3-5 days)
- Mild increase in energy or sense of well-being
- Possible mild joint or muscle achiness (growth phase discomfort)
What's normal
- Transient water retention (2-3 lbs weight gain is normal)
- Mild appetite stimulation without discomfort
- No dramatic changes in body composition (too early)
- Possible slight sleep improvement
What's next
- Assess tolerance at starting dose
- If well tolerated, prepare to increase to standard dose in Week 3
- Monitor for any concerning symptoms
- Establish consistent training and nutrition routine
Week 3-6
What you might notice
- Gradual increase in lean muscle appearance (if training consistently)
- Better recovery between training sessions
- Sustained appetite stimulation
- Possible slight waist reduction (fat loss) depending on diet
What's normal
- Body weight stable or slight increase (muscle gain + water retention)
- Continued mild joint aches or 'growing pains' (usually mild)
- Improved sense of vitality and mood
- Possible slight insulin resistance (check fasting glucose if diabetic)
What's next
- If at standard dose with good tolerance, may remain there through Week 12
- If minimal effects seen, consider dose increase to advanced tier in Week 7
- Continue progressive resistance training for compound to work optimally
- Monitor blood glucose if at risk for diabetes
Week 7-12
What you might notice
- More noticeable lean mass gains (expect 2-4 lbs per month of true muscle)
- Visible improvement in muscle definition and vascularity
- Sustained recovery and reduced muscle soreness
- Possible body weight increase of 5-12 lbs depending on diet
What's normal
- Appetite remains elevated throughout cycle
- Transient water retention may persist (normal with GH stimulation)
- Continued modest improvements in training performance
- Energy levels sustained at elevated baseline
- No major escalation of side effects if dose stable
What's next
- At Week 10-12, begin planning cycle off (taper not necessary for oral compound)
- Discontinue and allow GH levels to normalize (takes 2-4 weeks)
- Maintain training and nutrition to preserve gains
- Take 4-8 week break before considering re-dosing (limited human data on cycling)
- Have follow-up bloodwork if possible, especially glucose and IGF-1
Signs it's working
Physical performance
- Improved strength gains during progressive resistance training
- Faster recovery between training sessions (less delayed muscle soreness)
- Increased training volume capacity (can do more reps or sets at same intensity)
- Better endurance and reduced fatigue during workouts
Body composition
- Visible increase in muscle size and definition (especially arms, shoulders, chest)
- Decrease in body fat percentage (with proper diet) despite weight increase
- Improved muscle separation and vascularity
- Waist remains stable or slight decrease while weight increases (indicator of muscle gain)
General well-being
- Increased appetite and food enjoyment
- Elevated mood and sense of well-being
- Improved energy throughout the day
- Better sleep quality and duration
Not seeing results? Common reasons
- Inadequate resistance training stimulus (SM-130686 amplifies training effect; must train hard)
- Poor diet with insufficient protein (need 1-1.2g per lb body weight to capitalize on GH effect)
- Inconsistent dosing schedule or missed doses (daily consistency is critical)
- Tolerance developed or low bioavailability absorption (take with meals; ensure digestive health)
- Unrealistic expectations or too-short cycle (results appear over 6-8 weeks; faster gains than natural but not overnight)
Key research
Questions
Frequently asked
Is SM-130686 legal?
SM-130686 is a research compound that has never been FDA-approved for human use. It does not have an established legal status. If it were commercially available, legality would depend on jurisdiction and regulatory classification. It is not approved in any country for human consumption. Most importantly: there is no human safety data. Using any unapproved research compound carries legal and health risks.
How does SM-130686 compare to MK-677 (Ibutamoren)?
Both are oral GHS-R agonists. MK-677 has far more human research (Phase 2/3 studies completed) and established safety profile, while SM-130686 is preclinical only. MK-677 is a full agonist (~100% activity), while SM-130686 is a partial agonist (~55%). MK-677 may produce stronger GH stimulation but also greater side effect risk. SM-130686 may offer more physiological GH pulsatility (theoretical advantage) but is completely unstudied in humans. If comparing, MK-677 has better evidence, but both are research compounds.
Can I take SM-130686 if I have diabetes?
Not recommended without medical supervision. GH antagonizes insulin action and increases blood glucose. Diabetic individuals would need to adjust insulin doses, monitor glucose closely (multiple times daily), and consult their endocrinologist. Even then, the unknown effects of SM-130686 in diabetics make it high-risk. Risk of severe hyperglycemia or diabetic complications is real. Avoid use unless under direct medical monitoring by a diabetes specialist.
How long does it take to see results?
Based on rat studies: appetite stimulation within 3-5 days, initial water retention (2-3 lbs) within 1-2 weeks, noticeable lean mass gains by Week 4-6 if training hard. Meaningful body composition changes (muscle definition, fat loss) typically appear around Week 6-8. Maximum effects in rat studies occurred after 8-9 weeks of consistent dosing. Individual response varies. Results depend heavily on diet quality, training intensity, and genetics. Do not expect overnight transformation.
What's the difference between SM-130686 being a partial agonist vs. full agonist?
A partial agonist (SM-130686 at ~55% activity) activates the receptor to ~55% of maximum, while a full agonist activates it to 100%. In theory, partial agonism may produce more natural, pulsatile GH secretion mimicking your body's own rhythm, potentially safer. Full agonists like MK-677 produce stronger GH spikes, faster results, but potentially more side effects. Trade-off: SM-130686 might be more physiological but weaker; full agonists more powerful but riskier. Neither has been tested head-to-head in humans.
Do I need to cycle off SM-130686?
Unknown. No human studies exist on long-term use or optimal cycling protocols. For oral compounds, taper is not necessary on discontinuation (unlike testosterone). Reasonable approach based on GH physiology: 8-12 week cycles with 4-8 week breaks allows hypothalamic-pituitary axis recovery and prevents potential tolerance. Continuous use risks developing receptor desensitization, but this is theoretical. Consult a knowledgeable physician if available. Conservative cycling approach is safer given unknown long-term effects.
Further reading
History & related research
History · since 2001
The Oxindole That Could Have Been — A Ghost from the Chemical Library
SM-130686 is a small-molecule chemical compound (not a peptide) that was designed to mimic ghrelin, the body's natural hunger hormone. Created by Sumitomo Pharmaceuticals in Japan, it was one of the first compounds that could be taken by mouth to trigger growth hormone release.
Read the full history of SM-130686Ready for the protocol?
Every dosing tier, administration route, timing note, and dose-adjustment rule for SM-130686, on one page.