Ibutamoren (MK-677)
MK-0677, MK677, Ibutamoren mesylate, LUM-201
Oral, non-peptide ghrelin mimetic (GH secretagogue) that raises GH and IGF-1. Tested in clinical trials but never approved.
Legal status: Unapproved drug sold as a 'research chemical'; FDA lists it as a significant safety risk (heart failure). Status varies by country.
What it gives
What people use it for and what the sources report. Strength is a general category from the literature: mild, clear or strong.
Purpose
Studied for age-related muscle loss, hip-fracture recovery and GH deficiency, including in children. In sport: a 'research chemical' used for appetite, sleep and mass; in trials lean mass and water rose, but strength did not.
What people seek and what studies show
Used for appetite, sleep and weight gain. In a year-long trial in older adults it raised IGF-1 to young-adult levels: weight rose about 2.7 kg (0.8 kg on placebo) and fat-free mass about 1 kg, limb fat also increased, and visceral fat did not fall. In a small study in young adults deep sleep lengthened by about half; in volunteers on a strict diet it reversed protein loss within a week. No studies in athletes exist.
Effects
Evidence: Limited human data — some human studies, small or short
Sought effects by goal (as reported)
Possible side effects
Possible does not mean certain: whether they appear depends on dose, duration, individual response and monitoring. Below — what to watch for and how to notice it early.
9 possible side effects
level · how often it is reportedWhat the levels mean
Level: general category from the literature, not your personal risk
How often
- common
- reported often
- possible
- reported in some people
- rare
- reported occasionally
How to lower the risks
For 6 of 9 possible side effects there are specific ways to lower the chance: everyday measures, supplements and options a doctor may consider. For the rest — general advice. No measure removes a risk completely. Prescription medicines are listed only for a doctor to decide on, after tests — they have side effects of their own.
Regular cardio, blood pressure control, an echo as a baseline and then yearly.
How each option helps (9)
- Heart screening: ECG and echocardiogram — Echocardiography shows wall thickening and reduced pumping early, while stopping AAS and treating BP can still help.
- Working with a doctor — Orders ECG and echocardiography and treats early heart changes.
- Home blood-pressure monitoring — Keeping BP controlled is one of the main ways to limit heart-wall thickening.
- Regular cardio training — Supports heart and vessel function, but does not reverse steroid-related heart thickening or weakening.
- ACE inhibitors (ramipril, perindopril, lisinopril) — Standard treatment for a weak heart (heart failure), and shrinks a thickened heart wall about as well as other BP drugs. Not studied in steroid users; the steroid risk remains. Has side effects of its own.
- Bisoprolol — In heart failure with weak pumping it lowered deaths in trials; doctors add it to standard therapy. Not studied in steroid users; the steroid risk to the heart remains. Has side effects of its own.
- Carvedilol — A doctor may add it when tests show weak heart pumping; in heart failure it lowered deaths. Not studied in steroid users, and it does not undo steroid damage. Has side effects of its own.
- Losartan / valsartan (angiotensin receptor blockers) — In high blood pressure, sartans shrink a thickened heart wall at least as well as other BP drugs. Not studied in steroid users; the steroid risk to the heart remains. Has side effects of its own.
- Telmisartan — In high blood pressure, ARBs shrink a thickened heart wall at least as well as other BP drugs. Not studied in steroid users; the steroid risk to the heart remains. Has side effects of its own.
More daily movement, fewer fast carbs, check fasting glucose and HbA1c.
How each option helps (7)
- Glucose monitoring — Rising fasting readings reveal insulin resistance from GH or other drugs early.
- Regular blood tests — Fasting glucose, insulin and HbA1c catch rising blood sugar early — key with GH, its secretagogues and insulin.
- Regular cardio training — Improves insulin sensitivity — useful against the blood-sugar rise from GH and its secretagogues.
- Working with a doctor — Interprets glucose markers and treats early metabolic problems.
- Berberine — Meta-analyses: lower fasting glucose and HbA1c (about 0.6% in type 2 diabetes); smaller effect when glucose is normal.
- Alpha-lipoic acid — Small drops in fasting glucose, insulin and HbA1c in meta-analyses; no real counter to GH- or insulin-driven resistance.
- Psyllium husk fiber — Slows sugar absorption: lower fasting glucose and HbA1c, mostly in people with diabetes.
Products obtained without a prescription are often fake, mislabeled or non-sterile, and there is no way to check at home. For legal supplements, look for third-party testing (Informed Sport, NSF).
No check-up or blood test lowers this risk; avoid with any personal or family history of cancer.
Low-level side effects
How each option helps (1)
- Working with a doctor — Tells harmless water retention from swelling due to heart, kidney or liver trouble; steroid labels warn that edema can come with heart failure.
How each option helps (2)
- Working with a doctor — Finds the cause of joint or muscle pain — estradiol pushed too low by an aromatase inhibitor, GH-driven swelling, statin muscle effects — so treatment can be adjusted.
- Coenzyme Q10 — May ease statin-related muscle aches (one meta-analysis positive, results mixed); no help for joint pain from low estrogen.
How each option helps (1)
- Working with a doctor — Finds treatable causes of numbness early: low vitamin B12 on metformin, copper deficiency from excess zinc, nerve compression from GH-driven swelling.
How each option helps (1)
- Regular blood tests — Prolactin testing matters with 19-nor compounds and helps explain low libido or nipple discharge.
Check-ups and blood tests
Which tests and check-ups to do and when. This is a guide — agree the exact schedule with your doctor.
Which doctors can help
At home
- Home blood pressure: 2–3 times a week in the morning, keep a log
Get medical help at once if
- Chest pain or pressure, breathlessness on light effort, swollen ankles, fainting — seek urgent care.
- A new lump (including in the neck), trouble swallowing or persistent hoarseness, unexplained weight loss, or blood in stool or urine — see a doctor promptly.
In an emergency, call your local emergency number.
Myth & fact
“MK-677 is a SARM.”
No. It does not act on androgen receptors: it mimics the hunger hormone ghrelin to raise GH and IGF-1, so its effects are ghrelin- and GH-type — hunger, water retention, higher blood sugar.
Combinations
No specific combination notes for this substance yet. The stack check still adds up side effects that several substances share.
Sources
Possible side effects by body system, combinations, how to lower the risks and which tests to do — free.
Open the stack check