HGH in a Pill? The ULTIMATE Guide to MK-677
Chemical Names
MK-677, Ibutamoren, Oratrope, L-163, L-191
Research Applications
Lean mass gain
Fat loss
Muscle retention
Appetite stimulation
Sleep quality enhancement
Recovery enhancement
Anti-aging
🍆 growth
Correcting growth hormone deficiency
What is MK-677?
MK-677, also known as ibutamoren mesylate, is an orally active, non-peptide growth hormone secretagogue and a ghrelin receptor agonist. It selectively stimulates the pituitary gland to release growth hormone (GH), elevating serum HGH and IGF-1 levels.
Nominated for the treatment of growth hormone deficiency (GHD), including adult-onset GHD and catabolic conditions, MK-677 has been studied for its potential benefits in bone strengthening, muscle gain, fat loss, and sleep quality improvement.
Although it’s non-steroidal and non-androgenic, it’s often mistakenly classified as a selective androgen receptor modulator (SARM) and sold by vendors that sell SARMS.
MK-677 does not negatively impact natural testosterone levels or endocrine function, nor does it suppress male sex hormones.
Unlike reconstituted HGH or peptides, MK-677 has a much longer shelf life and does not need storage in cold conditions.
As of now, there are no FDA-approved products containing ibutamoren mesylate, and MK-677 is classified as an Investigational New Drug in the United States, but Clinical trials are evaluating MK-677's efficacy as a treatment for growth hormone deficiencies, muscle-wasting diseases, osteoporosis, and other related conditions.
Currently, MK-677 is available via compounding pharmacies to patients of cutting-edge clinics, like Marek Health, and to researchers as a reference material.
Benefits of High IGF-1 Levels
Increase in muscle mass
Increased in energy
Improved nutrient partitioning (more food into muscle, less into fat)
Enhanced recovery
Enhanced sleep quality
Enhanced cosmetic appearance (youthful skin, hair, and nails)
Note on IGF-1’s Anabolic Effect:
Muscle mass can increase through two main mechanisms: hypertrophy, which is the enlargement of myofibres, and hyperplasia, which is the increase in the number of myofibers. However, muscle growth is typically limited to hypertrophy, where existing muscle fibers increase in size. (even with the use of anabolic steroids)
IGF-1, on the other hand, enhances muscle gains through both mechanisms. IGF-1 facilitates the creation of new muscle cells by promoting cellular division (hyperplasia), making it unique among hormones in this capacity. Hyperplasia expands an individual's genetic potential for muscle growth and is thought to create “permanent muscle gains” to some degree.
Elevated IGF-1 levels are the icing on the anabolic cake when combined with resistance training, proper nutrition, insulin sensitivity, and high androgen levels.
How Much Can MK-677 Increase IGF-1?
On average, MK-677 yields roughly equivalent IGF-1 levels as ~2iu of pharmaceutical-grade HGH. This response can be greater (up to 4iu+) or less depending on dosage, diet, baseline insulin sensitivity, estradiol levels, nutrient status, ancillary stack, use of GHRH agonists, sex, age, and genetics.
The evidence: In various clinical trials, MK-677 has shown significant increases in serum GH and IGF-1 levels.
3-Month Study on Hemodialysis Patients
A 3-month study on 26 patients with end-stage kidney disease, saw a 76% average increase in IGF-1 after treatment with 25mg of MK-677 per day. When accounting for baseline IGF-1 levels, the increase with MK-677 was 65% greater than with the placebo after 30 days.
The graph shows the ratio of IGF-1 and GH levels before and after the intervention, with circles marking the average ratio and vertical lines showing the range of values they’re confident in (95% confidence interval). The dashed line represents a ratio of 1, meaning no change.
2-Month Study on Obese Males
A two-month study on 24 obese males found that after two weeks of 25 mg of MK-677 daily, serum IGF-1 levels rose by approximately 40% compared to pre-treatment levels. This increase was maintained throughout the treatment period.
These graphs show the serum concentrations of IGF-1 and IGFBP-3 (IGF Binding Protein 3) during the treatment of obese males with either 25 mg of MK-677 or a daily placebo.
2-Year Study on Healthy Elderly Adults
In a two-year study with 65 healthy men and women aged 60-81, daily MK-677 notably raised GH and IGF-1 levels to those typically seen in healthy young adults without serious adverse effects.
Growth hormone (GH) and insulin-like growth factor I (IGF-I) levels at baseline and at 6 and 12 months, and a representative GH profile.
24-Hour Mean Serum GH Levels
Study on Severely GH-Deficient Men
Research involving nine severely GH-deficient men aged 17-34 showed that 10 mg of MK-677 increased serum IGF-1 levels by an average of 52% and GH levels by an average of 79%. A higher dose of 50 mg resulted in a 79% increase in serum IGF-1 levels and an 82% increase in GH levels.
24-hour Comparison of IGF-1 Levels in GH-Deficient Men: Placebo vs. 10 mg MK-677 vs. 50 mg MK-677
12-Month Study on Postmenopausal Osteoporotic Women
In a year-long study involving postmenopausal women with osteoporosis, a daily dose of 25 mg of MK-677, with or without alendronate (osteoporosis medication), increased IGF-1 levels by about 40%. However, after peaking in the first month, IGF-1 levels gradually decreased throughout the year. This suggests that using MK-677 in cycles might maximize its effectiveness; more on this later.
Changes in IGF-1 levels over 12 months of MK-677, Alendronate, MK-677 + Alendronate, and placebo administration.
MK-677 Dosing Ranges
10 to 12.5mg per day
Since MK-677 lacks an official recommended dosage, researchers often consult existing studies for guidance.
As shown in the studies above, a daily dose of 10 mg can substantially elevate IGF-1 levels by 52% and GH levels by 79% on average in GH-deficient men.
20 to 25mg per day
Doubling the dose to 20-25 mg daily can yield around 25% GH and IGF-1 levels, but a lot more side effects. Double dose does not mean double gainz doood. This higher dosage range can still be advantageous for enhanced muscle growth.
UM’s Personal Experience
I’ve given MK-677 a run multiple times and still use it now and then as a quick appetite booster or sleep aid. I’ve gotten my IGF-1 up to the low 400s on 12.5mg of MK-677 per day, though my levels are usually in the upper 200/low 300s naturally.
The hunger I experience on 20mg+ is out of control. I would eat 8oz of meat with 2 cups of rice and 2 cups of vegetables and an hour later I’d be starving again and able to eat another meal. I knew it was time to call it quits when I demolished a large 16” pizza to myself and was still hungry. Hence, I don’t think the upper dosages of MK-677 are worth it aside from hard gainers. Remember: IGF-1 levels on 25mg are only about 25% higher than 15.mg (more ≠ better)
A lower dose + a GLP-1 Agonists, particularly Retratrutide, would probably be the best bet if using MK-677 on a cut.
The water retention is quite substantial if you aren’t eating clean. I don’t think anyone should run this if their diet isn’t relatively dialed in. When I was eating takeout once or twice every day, I gained at least 10 lbs of water weight within the first week. The bloated appearance was so pronounced, that multiple people pointed it out and I’d have an indentation about a half-inch deep when I’d take my socks off after work. Due to the water retention, my blood pressure was quite elevated. I resolved the water retention by dropping down to 12.5mg, fasting for 2 days, and implementing a strict carb cycling diet (5 days keto, 2 days high carb/low fat)
I think if you’re going to do MK-677 right, it should look like this:
Get baseline, mid-cycle, and post-cycle bloodwork: CBC, CMP, IGF-1, Fasted Insulin, HbA1c, Prolactin
Use a glucometer upon waking, before meals, and 2 hours after meals to keep tabs on blood sugar levels and potential insulin resistance
Monitor blood pressure 3 times daily
Keep cycles to around 12 weeks if everything is going well (or just use it occasionally)
Make sure you have doctor's supervision & prescription
Stop if you aren’t feeling well or experiencing uncomfortable side effects
MK-677 Side effects / Risks
Increased Appetite
MK-677 significantly boosts appetite by activating ghrelin receptors. Ghrelin, known as the "hunger hormone," is effectively mimicked, tricking your body into being hungry even when it wouldn't have normally been. This often makes it challenging to maintain a calorie deficit. This effect is more pronounced due to MK-677's long duration of action compared to the ghrelin receptor agonist peptides.
Lethargy
Lethargy is a common and expected side effect. Higher levels of growth hormone (GH) and IGF-1, whether from synthetic GH injections, peptides, or secretagogues like MK-677, commonly cause increased levels of lethargy.
Vivid Dreams
Dreams occur during the REM phase of sleep. Through increased HGH secretion, MK-677 promotes an increase in REM sleep. This, in turn, improves sleep quality and can lead to some very vivid and sometimes bizarre dreams or nightmares.
Water Retention
Elevated GH and IGF-1 levels can lead to water retention, with common symptoms in clinical trials including transient edema and muscle pain due to stress on joints and muscles from intracellular water retention.
Increased Blood Pressure
Edema, one of the most common side effects of MK-677 use, can indirectly cause elevated blood pressure.
Elevated Blood Sugar & Reduced Insulin Sensitivity
Although various clinical studies found no change in blood glucose levels, few studies showed that MK-677 caused an increase in fasted blood glucose levels and reduced insulin sensitivity. GH causes blood sugar levels to elevate, resulting in the pancreas working harder to release insulin to combat this impact. Chronic blood glucose elevation and pancreatic cell degeneration are what eventually lead to type 2 diabetes, especially in individuals with other risk factors such as holding too much body fat or excessive carbohydrate intake.
Reactive Hypoglycemia
In insulin-resistant individuals, MK-677 can cause reactive hypoglycemia, characterized by sharp blood sugar spikes followed by excessive insulin release and a subsequent crash, leading to symptoms like hunger, weakness, shakiness, and lightheadedness.
Tingly or Numb Fingers and Hands
Elevated growth hormone levels can cause tingling or numbness in extremities, as reported anecdotally by users of MK-677. This is a common side effect.
Increased Anxiety
A study on rats showed that chronic ghrelin receptor stimulation by MK-677 increased fear memory, though this effect has not been observed in human trials. Some Redditors have reported increased anxiety, but this is typical on Reddit so it is unclear if this is due to the nocebo effect/hypochondria.
Ideal MK-677/Peptide Combos:
CJC-1295: GHRH Analogue for Higher HGH/IGF-1 Levels
CJC is a synthetic analog of growth hormone-releasing hormone (GHRH). While MK-677 stimulates GH release by imitating the action of ghrelin, CJC mimics the body's natural GHRH. Both compounds synergize to elevate IGF-1 levels.
Semaglutide: Appetite Suppressant and Glucose Control
Semaglutide suppresses appetite by mimicking the hormone GLP-1, which regulates appetite, glucose metabolism, and gastric emptying. Semaglutide can be an effective tool for offsetting the increase in hunger while using MK-677 on a cut or recomp. Since it slows gastric emptying, it’s not ideal to use on a bulk as that’s when the side effects like nausea and vomiting become more likely.
Retratrutide: Appetite Suppression, Glucose Control, and Insulin Sensitivity
Retratrutide is a triple agonist of the GIP, GLP-1, and glucagon receptors, and a superior alternative to semaglutide. It’s probably the ultimate support peptide that could be combined with MK-677 to counteract side effects. Retratrutide enhances insulin secretion in response to food intake, reduces glucose production in the liver, and slows down gastric emptying, which leads to lower post-meal blood sugar spikes, increased satiety, and lower appetite. Again, since it slows gastric emptying, it’s not ideal to use on a bulk as that’s when the side effects like nausea and vomiting become more likely.
5-Amino-1MQ (Fat loss & energy enhancement)
5-Amino-1MQ inhibits the enzyme nicotinamide N-methyltransferase (NNMT), which is linked to obesity and fat storage. By blocking NNMT, 5-Amino-1MQ can enhance a MK-677 cycle by further reducing body fat, increasing energy, and improving metabolic health.
MK-677 Support Supplements
Berberine (AKA Nature’s Metformin) is known for its ability to regulate blood sugar levels and insulin response partly by activating AMPK, an enzyme that plays a key role in managing cellular energy. This activation mimics the effects of fasting by increasing fat burning, improving glucose metabolism, and enhancing insulin response. It may also slightly improve IGF-1 levels on MK-677.
Cyanidin 3-Glucoside (C3G) is a powerful antioxidant found in purple foods like berries, red wine, and black rice. It enhances insulin sensitivity and nutrient partitioning, directing nutrients from food into muscles rather than fat, making it ideal for both bulking and cutting phases. It also can support energy levels and cognitive function, offsetting some of the MK-677 lethargy.
An advanced formulation of r-alpha lipoic acid (r-ALA) to enhance bioavailability and shelf life. r-ALA is essential for energy production and helps protect the mitochondria from oxidative stress, supporting overall cellular health, function, and energy metabolism on an MK-677 cycle.
Optional:
The ultimate Tribulus-based energy, stamina, focus, and DHT formula. Great for enhancing athletic performance, strength, and energy levels on MK-677.
Ultimate energy blend for hardcore stimulant enjoyers. Combines Dynamine/methylliberine, a fast-acting and potent caffeine analog, with regular caffeine, extended-release caffeine, delayed-release caffeine, and L-theanine for 8+ hours of reliable focus and energy.
MK-677 Benefits in Research
So far, the literature has shown strong evidence for MK-677’s effectiveness in the following:
Improvement in body composition (more muscle, less fat)
Improvement in sleep quality
Increase in bone strength
Improvement in Body Composition: Various short-term clinical studies demonstrated that MK-677 can positively influence body composition. Svensson et al. (1998) involved 24 obese men who were dieting and received either 25 mg of MK-677 or a placebo daily for eight weeks. Results showed those taking MK-677 experienced a 40% increase in serum insulin-like growth factor I (IGF-I) and significant increases in serum IGF-binding protein-3, particularly notable during the second and eighth weeks. The findings indicated that MK-677 promoted increases in lean body mass and caused a temporary rise in basal metabolic rate. Further investigations with higher doses or extended treatment durations could provide greater insights into potential effects on body fat levels.
In 8 weeks, obese subjects on MK-677 gained roughly 6 lbs of lean mass while losing around a half lb of fat WITHOUT dieting or exercising (don’t do this LOL). The other group that didn’t take MK-677 lost muscle and gained fat.
Enhancement of Sleep Quality and Duration: A 1997 study assessed the impact of MK-677 on sleep among eight young participants aged 18 to 30. Each participant underwent three treatment periods of seven days each, receiving bedtime doses of MK-677 (at 5 mg and 25 mg) or a placebo.
Results showed that MK-677 significantly improved sleep, with a 50% increase in the duration of stage IV sleep and over a 20% increase in REM sleep compared to the placebo group. Researchers concluded that MK-677 may enhance sleep quality while also addressing relative hyposomatotropism of senescence.
Support for Bone Formation and Resorption: Additional research has explored MK-677’s influence on bone health. A paper known as the “MK-677 Study Group” reported results from three separate trials investigating MK-677’s effects on bone turnover among healthy and functionally impaired elderly adults.
The first trial involved 32 healthy seniors receiving either 10 or 25 mg of MK-677 or a placebo.
The second trial studied 50 healthy adults aged 65-85, who were given either 25 mg or 50 mg of MK-677 or a placebo, while the third involved 105 elderly patients with functional impairment aged 65-94, who received doses of 5 mg, 10 mg, or 25 mg of MK-677 or a placebo.
The reports show that once-daily administration of MK-677 stimulates bone turnover in the elderly.
A randomized, double-blind trial also supports the short-term treatment of MK-677 increased bone formation and resorption markers; however, further long-term studies were necessary to assess the impact of MK-677 on bone mass.
Best Source for MK-677
The majority of the peptide and research chemical companies out there are shady. Unfortunately, importing pre-manufactured products from Chinese vendors with little to no quality control, undesirable fillers and byproducts, lack of transparency/testing, and poor customer service is the industry standard. That’s why Limitless Biotech is my go-to source for peptides and research compounds:
Unmatched Quality & Transparency: Limitless Life utilizes third-party lab tests, including HPLC-MS analysis, to guarantee that each batch of MK-677 is of the highest purity (>99%) and potency.
Fast Shipping: Limitless offers express shipping with a delivery promise of 24-48 hours, along with other shipping options for flexibility.
Great Customer Service: Fast responses from helpful and knowledgeable individuals who truly care about their customers
American Made: Limitless’s products are manufactured in a US-based GMP facility where meticulous sanitary processes and advanced purification processes are deployed to yield over 99% pure products every time.
Best Bang for Your Buck: Coupon code BOWTIED gets you 15% off
Other Links: CJC-1295, Semaglutide, Retratrutide, 5 Amino 1MQ
Gonna give this a try! 40yrs old and looking for better recovery.
Could I alternate cycles of CJC/IPA or Tesamorelin, then do a cycle of MK-677 ?