Can you buy ibutamoren in the UK? The short answer is that Free Muscle sells it for laboratory research use only, to customers aged 18 or over, and that the legal position has to be pieced together from several laws rather than one label. This ibutamoren UK guide covers the three practical questions behind that answer: what the law says, how anyone can tell whether a bottle contains what the label says, and what ordering involves. It answers them in plain English, using primary legislation, regulator pages and published research. Ibutamoren, also written MK-677 or MK-0677, is an investigational compound that Free Muscle sells for laboratory research use only, not for human consumption. Listings (laboratory research only, 18+): MK-677 capsules compared.
Key takeaways
- Ibutamoren was not found by name in Schedule 2 of the Misuse of Drugs Act 1971 text checked on 2 October 2026. That is not the same as saying every sale is lawful, because medicines law and other rules also apply.
- Under the Human Medicines Regulations 2012, a substance may count as a medicinal product depending on how it is presented and whether it may be used by or administered to humans to modify a physiological function. Whether ibutamoren falls within that definition is a legal interpretation, not something the legislation pages state.
- A 2021 structural paper (Liu et al.) calls ibutamoren an investigational new drug. One hip-fracture trial was terminated early over a heart failure signal, and two other trials reported no significant clinical or functional benefit on their main measures.
- A Certificate of Analysis (COA), as a commonly used check, is only useful if it names the laboratory, the compound, the method, a batch number that matches the label and a date.
- Research compounds sold by Free Muscle are supplied for laboratory research use only and are not for human consumption. They are not authorised as medicines by the MHRA, EMA or FDA, are not food supplements, and are sold only to adults aged 18 or over. Nothing on this page is medical or dosing advice.
- This is general information, not legal advice, and nothing here is medical advice.
Ibutamoren UK legal status: is it legal?
A common question is whether MK-677 is legal in the UK. The law does not give one single label to this compound, so the position on selling ibutamoren in the UK has to be built from several pieces. Everything below comes from legislation we fetched and read, or from regulator pages linked here. This is general information, not legal advice.
Misuse of Drugs Act 1971
The Act sorts controlled drugs into Classes A, B and C through its schedules. We searched the text of Schedule 2 of the Misuse of Drugs Act 1971 for "ibutamoren", "MK-677" and "secretagogue" and found no match. So ibutamoren is not listed in the Schedule 2 text we checked on 2 October 2026. This shows absence from one schedule only. The Act can be amended by orders, and it says nothing about other legislation.
Human Medicines Regulations 2012
Regulation 2 defines a medicinal product as a substance presented as having properties of preventing or treating disease in human beings, or one that may be used by or administered to humans to restore, correct or modify a physiological function through a pharmacological, immunological or metabolic action. Regulation 46 says a person may not sell, supply or offer to sell or supply an unauthorised medicinal product, and that a medicinal product must be sold in accordance with a UK marketing authorisation or one of the other listed routes.
Neither page says whether ibutamoren is a medicinal product or whether it has an authorisation. Regulation 2 refers both to how a product is presented and to whether it may be used by or administered to humans to modify a physiological function. Whether it applies to ibutamoren is a legal interpretation we do not make. One 2021 paper describes ibutamoren as an investigational new drug (Liu et al., 2021), and we found no marketing authorisation in anything we read. We did not check a regulator register, so we do not state a registry fact either way.
Psychoactive Substances Act 2016
Section 2 of the Psychoactive Substances Act 2016 defines a psychoactive substance by its capacity to produce a psychoactive effect, meaning stimulating or depressing the central nervous system and affecting mental functioning or emotional state. The page does not say whether ibutamoren is or is not covered, and we make no claim either way.
What the MHRA says in general terms
In a press release dated 3 August 2016, the MHRA said its Medicines Borderline section had reviewed sports supplement companies and found 69 unauthorised medicines sold as sports supplements, with 16 companies selling one or more of them. This compared with 128 unauthorised medicines and 36 websites found before the 2012 Olympics. It also said some sports and body-building products on sale in the UK are found unacceptable even if considered legitimate in other countries, and it advised buyers of medicines online to look for the distance selling logo. The release is general and does not mention ibutamoren.
Sport and anti-doping
UK Anti-Doping explains that the WADA Prohibited List is updated every year with effect from 1 January, that peptide hormones and anabolic agents are prohibited at all times, and that substances not named can still be prohibited if they are similar in structure or biological effect. Athletes are strictly liable for anything found in their system, whatever the route or intent. The page text we extracted does not name ibutamoren, so anyone subject to sport testing should check the current WADA Prohibited List and ask the relevant body directly.
The position for the other compounds we stock, side by side: Are SARMs legal in the UK? 2026 guide
What "research use only" means, and what it does not
At Free Muscle, "research use only" means the compounds are sold for laboratory research use only, to customers aged 18 or over, and not for human consumption. In plain terms:
- Research compounds are sold for laboratory research use only, to customers aged 18 or over.
- They are not medicines and not food supplements, and Free Muscle does not sell ibutamoren as a food supplement.
- They are not for human consumption, and nothing on the site or in this article is medical advice.
Regulation 2 of the Human Medicines Regulations, linked above, refers to how a product is presented and, separately, to whether a substance may be used by or administered to humans to modify a physiological function. Whether a "research use only" label affects the legal position is a question we do not answer. This is general information, not legal advice. This article therefore contains no dosing, schedules or protocols. Anyone unsure about a specific situation should take proper legal advice.
What researchers and regulators say
This section summarises published evidence, because anecdotal reports from forums or sellers are not evidence. Every result below describes what happened to a named study population in a named study. None of it describes what would happen to a reader. The trials were run in specific populations and settings described in each paper (healthy older adults, obese men, hip-fracture patients, people with Alzheimer disease and others), so their results cannot be assumed to apply to any commercial capsule. Where the abstracts state the route, it was oral (Chapman, Nass, Svensson); protocol details are in each linked paper and are not repeated here.
How it works, according to the literature
Ibutamoren is a non-peptide agonist of the ghrelin receptor, also called GHSR. Smith (2005) reviewed how growth hormone secretagogues were developed by reverse pharmacology and described four routes by which they raise growth hormone pulses. Liu et al. (2021) reported cryo-EM structures of the receptor bound to ghrelin and to ibutamoren, which they called an investigational new drug. These are structural and molecular findings, not outcomes in people.
What measured outcomes looked like in trials
In a randomised, placebo-controlled trial of 32 healthy people aged 64 to 81, with placebo and three dose levels, Chapman et al. (1996) reported that, in the highest-dose group (the dose levels are given in the paper), mean 24-hour growth hormone rose by 97% from baseline after two weeks and serum IGF-I rose from 141 to 265 micrograms/L at four weeks. The same paper recorded fasting glucose rising from 5.4 to 6.8 mmol/L at four weeks (P < 0.01 versus baseline). Growth hormone concentrations rose in a dose-dependent manner, so lower-dose groups showed smaller increases.
In a two-year, double-blind trial of 65 healthy adults aged 60 to 81, Nass et al. (2008) reported that fat-free mass changed by -0.5 kg in the placebo group and +1.1 kg in the ibutamoren group at 12 months, while body weight rose 0.8 kg versus 2.7 kg. Fasting glucose rose on average by 0.3 mmol/L and insulin sensitivity fell. The most frequent side effects were increased appetite, transient mild lower-limb oedema and muscle pain. The authors also reported that the gain in fat-free mass did not translate into changes in strength or function.
In 24 obese men over eight weeks, Svensson et al. (1998) found IGF-I up about 40% and higher fat-free mass on DXA, but no significant change in total or visceral fat, and a glucose tolerance test showed impaired glucose handling at weeks 2 and 8.
Where trials found limited functional benefit, or a safety signal
- Bach et al. (2004) randomised 161 hip-fracture patients for six months. IGF-I rose 84% versus 17% on placebo, yet there were no significant differences in functional performance or the overall SIP-NH score.
- Adunsky et al. (2011) studied 123 elderly hip-fracture patients. The trial was terminated early because of a safety signal of congestive heart failure in a limited number of patients, and the authors concluded the safety profile was unfavourable in that population. The abstract also reported a difference in gait speed and no improvement in several other functional measures.
- Sevigny et al. (2008) randomised 563 people with mild to moderate Alzheimer disease for 12 months. Serum IGF-1 rose 72.9% at 12 months, but none of the four clinical scales differed from placebo, and the authors called it ineffective at slowing progression.
Case reports and market surveillance
Cobani et al. (2025) described one man in his early thirties who developed raised liver enzymes after taking MK-677 as a supplement; the enzymes returned to normal after he stopped. Chong et al. (2024) reported a 40-year-old man with gynaecomastia and hypogonadotropic hypogonadism linked to products found to contain several compounds, including MK-677, plus undisclosed hormones, so the effects cannot be pinned on one ingredient. These are single case reports and say nothing about how common any problem is.
On quality, Barrios et al. (2025) reported market surveillance by laboratories in the General European OMCL Network (GEON): 324 samples reported from 13 countries, mostly from illegal distribution. Eighteen molecules were reported, and ibutamoren was listed first of the top five. Sixty-five per cent of seized products were represented as medicines and 24% as dietary supplements. Across all samples in the study (SARMs, metabolic modulators and growth hormone secretagogues together), the authors assumed from limited quantitative data that most contained active doses and some were overdosed, so health risks for consumers could not be neglected.
Sigalos and Pastuszak (2018) reviewed clinical studies of growth hormone secretagogues, a class that includes ibutamoren, and noted few long-term, rigorously controlled studies, some concern about blood glucose through reduced insulin sensitivity, and a need for long-term safety data including cancer incidence and mortality. For the full study-by-study review, read our MK-677 research review.
How to judge quality: the Certificate of Analysis explained
A Certificate of Analysis is a document from a testing laboratory that reports what it measured in a specific batch. The two measurements commonly checked are identity (is it the right molecule?) and purity (how much of what was measured is that molecule?). The notes and table below describe commonly used checks and are general laboratory practice, not Free Muscle policy. Commonly used checks include the items in the table, and plain definitions help here: HPLC (high-performance liquid chromatography) separates the components of a sample so each can be measured, and mass spectrometry weighs the molecules, which helps confirm identity. For a longer walk-through, see how to read a Certificate of Analysis.
| What to check | What it tells you | Red flag |
|---|---|---|
| Named laboratory | Who actually performed the testing, and whether you can contact them to verify. | No lab name, a logo only, or a lab that cannot be found. |
| Compound name and identity method | That mass spectrometry or a comparable method confirmed the molecule is ibutamoren and not something else. | Purity stated with no identity evidence, or a different compound name. |
| Purity by HPLC | The share of the measured signal attributable to the target compound, shown as a percentage with a chromatogram. | A round number with no chromatogram, or a figure above 100%. |
| Batch number | That the report belongs to the material in your hand when it matches the number printed on the label. | No batch number, or one that differs from the label. |
| Test date | That the testing is recent and tied to this production run. | No date, or a date long before the batch could exist. |
| Sample description | What form was tested (powder, capsule contents) and the declared strength. | Vague wording that does not match the product listing. |
| Consistency between batches | Whether results are reproducible rather than a single flattering report. | Identical reports reused for different batches. |
A COA proves only what it says about the sample tested. It is not a guarantee of how a product behaves, and it says nothing about legality. It is a quality document, which matters given the surveillance findings above, in which the authors judged from limited quantitative data that most of the suspected illegal products studied (covering several compound classes, not ibutamoren alone) contained active doses and some were overdosed.
How batch testing works at Free Muscle
Every Free Muscle batch of research compounds is assayed for identity and purity by Janoshik Analytical, an independent laboratory. You can read more in our explainer on what Janoshik Analytical is and the lab tests page.
The Certificate of Analysis for a batch is sent on request. Email the batch number printed on the label together with the product name, and the certificate for that batch is returned. Matching the batch number on your bottle with the one on the document is the key step, and it is the same check described in the table above.
How to order from Free Muscle, step by step
The steps below apply to any ibutamoren order placed through the Free Muscle site.
- Choose the listing. Open the MK-677 ibutamoren collection and choose the listing that matches your laboratory records. Each product page states the strength per capsule and the number of capsules.
- Add to basket and check out. Review the basket, enter your delivery details and complete checkout.
- Age. Research compounds are sold only to customers aged 18 or over.
- Processing. Orders placed before 2pm UK time, Monday to Friday, are processed the same working day.
- Delivery. UK delivery is free and tracked, in plain packaging. Standard UK delivery takes 2 to 5 working days. Full details are on the shipping page.
- On arrival. Find the batch number printed on the label. Keep the item sealed if you may need to return it.
- Request the COA. Email the batch number and the product name to receive that batch's certificate.
- Returns. Unopened items in their original packaging can be returned within 30 days, as set out on the guarantee page. Apparel returns follow the refund policy.
The conditions above apply to every ibutamoren listing on the site: the material is for laboratory research use only.
Ibutamoren UK listings: strengths and pack sizes
Free Muscle lists ibutamoren capsules in three strengths, each in a bottle of 60 capsules. Strengths are label declarations only; Free Muscle does not recommend a strength.
| Listing | Strength per capsule | Capsules |
|---|---|---|
| MK-677 Ibutamoren 10mg, 60 capsules | 10mg | 60 |
| MK-677 Ibutamoren 12.5mg, 60 capsules | 12.5mg | 60 |
| MK-677 Ibutamoren 25mg, 60 capsules | 25mg | 60 |
When you receive a bottle, read the label in this order: product name, strength per capsule, capsule count, batch number. Then compare the batch number and the declared strength with the COA you requested. If the strength on the certificate does not match the strength on the label, contact the seller. All three listings are shown together in the collection linked in the ordering steps above.
Record-keeping for laboratory materials
These are record-keeping points tied to the ordering process described above.
- Keep the original label. Keep the label with its batch number legible.
- Record the date received. Note it alongside the batch number.
- Keep records together. File the COA with your purchase record.
- Keep sealed items unopened if a return may be needed. Free Muscle accepts returns of unopened items in their original packaging within 30 days.
Frequently asked questions
Can you buy ibutamoren in the UK?
Free Muscle sells ibutamoren in the UK for laboratory research use only, to customers aged 18 or over. It is not a medicine or a food supplement and is not for human consumption. On the law, ibutamoren was not found by name in Schedule 2 of the Misuse of Drugs Act 1971 text we checked, but whether a given sale is lawful also depends on medicines law such as the Human Medicines Regulations 2012, which is a legal interpretation we do not make. Ordering follows the steps set out above: choose a listing, check out, then request the Certificate of Analysis for the batch number on the label. This is general information, not legal advice.
Is ibutamoren legal in the UK?
On UK law, ibutamoren was not found by name in Schedule 2 of the Misuse of Drugs Act 1971 text we checked on 2 October 2026. Whether a given sale is lawful also depends on medicines law such as the Human Medicines Regulations 2012, which refers to how a product is presented and whether it may be used or administered to humans to modify a physiological function. This is general information, not legal advice.
Is MK-677 a controlled drug?
We did not find it listed by name in the controlled drugs schedule we checked. That covers one schedule only, and orders can amend the Act, so check current legislation if the point matters to you. This is general information, not legal advice.
What does "research use only" mean?
It means the item is supplied for laboratory research, to customers aged 18 or over, and is not a medicine, not a food supplement and not for human consumption.
How do I know the product is what the label says?
Ask for the Certificate of Analysis for your batch and check that the laboratory, compound name, identity method, purity result, date and batch number all line up with the label.
Who tests Free Muscle batches?
Every batch of research compounds is assayed for identity and purity by Janoshik Analytical, an independent laboratory.
How do I get the COA?
Email the batch number printed on the label together with the product name. Details are on the lab tests page linked above.
How long does UK delivery take?
For a UK order, standard delivery takes 2 to 5 working days, it is free and tracked, and it arrives in plain packaging. Orders placed before 2pm UK time Monday to Friday are processed the same working day.
Can I return an order?
Unopened items in their original packaging can be returned within 30 days. See the guarantee page linked in the ordering steps for the conditions.
Is there an age limit?
Yes. Research compounds are sold only to customers aged 18 or over.
Is ibutamoren a food supplement?
No. Free Muscle's ibutamoren is a research compound, not a food supplement. Free Muscle's two food supplements, CREATREN and NitraGlyc, are separate products.
Where can I read the research?
The studies are linked in the sources below, and our research review, linked in the research section above, goes through them one by one.
Notice. This article is published by Free Muscle, which sells the research compounds discussed. Research compounds sold by Free Muscle are supplied for laboratory research use only and are not for human consumption. They are not authorised as medicines by the MHRA, EMA or FDA, are not food supplements, and are sold only to adults aged 18 or over. Nothing on this page is medical or dosing advice. This is general information, not legal advice.
Sources
- Chapman IM, Bach MA, Van Cauter E, et al. Stimulation of the growth hormone (GH)-insulin-like growth factor I axis by daily oral administration of a GH secretogogue (MK-677) in healthy elderly subjects. J Clin Endocrinol Metab. 1996;81(12):4249-57. doi:10.1210/jcem.81.12.8954023 PMID 8954023
- Nass R, Pezzoli SS, Oliveri MC, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008;149(9):601-11. doi:10.7326/0003-4819-149-9-200811040-00003 PMID 18981485
- Svensson J, Lönn L, Jansson JO, et al. Two-month treatment of obese subjects with the oral growth hormone (GH) secretagogue MK-677 increases GH secretion, fat-free mass, and energy expenditure. J Clin Endocrinol Metab. 1998;83(2):362-9. doi:10.1210/jcem.83.2.4539 PMID 9467542
- Bach MA, Rockwood K, Zetterberg C, et al. The effects of MK-0677, an oral growth hormone secretagogue, in patients with hip fracture. J Am Geriatr Soc. 2004;52(4):516-23. doi:10.1111/j.1532-5415.2004.52156.x PMID 15066065
- Adunsky A, Chandler J, Heyden N, et al. MK-0677 (ibutamoren mesylate) for the treatment of patients recovering from hip fracture: a multicenter, randomized, placebo-controlled phase IIb study. Arch Gerontol Geriatr. 2011;53(2):183-9. doi:10.1016/j.archger.2010.10.004 PMID 21067829
- Sevigny JJ, Ryan JM, van Dyck CH, et al. Growth hormone secretagogue MK-677: no clinical effect on AD progression in a randomized trial. Neurology. 2008;71(21):1702-8. doi:10.1212/01.wnl.0000335163.88054.e7 PMID 19015485
- Cobani E, Amin MS, Hasso M, Kumbar L. Hepatotoxicity induced by MK-677. BMJ Case Rep. 2025;18(7). doi:10.1136/bcr-2025-265728 PMID 40675653
- Chong S, Woolnough CA, Koyyalamudi SR, Perera NJ. Reversible gynecomastia and hypogonadism due to usage of commercial performance-enhancing supplement use. JCEM Case Rep. 2024;2(8):luae148. doi:10.1210/jcemcr/luae148 PMID 39145153
- Barrios MM, Deconinck E, Vanhee C, et al. SARMs, metabolic modulators and growth hormone secretagogues in suspected illegal medicines, bought as sport performance enhancers: a retro- and prospective study within the GEON. Drug Test Anal. 2025;17(10):2078-2085. doi:10.1002/dta.3918 PMID 40551438
- Sigalos JT, Pastuszak AW. The safety and efficacy of growth hormone secretagogues. Sex Med Rev. 2018;6(1):45-53. doi:10.1016/j.sxmr.2017.02.004 PMID 28400207
- Smith RG. Development of growth hormone secretagogues. Endocr Rev. 2005;26(3):346-60. doi:10.1210/er.2004-0019 PMID 15814848
- Liu H, Sun D, Myasnikov A, et al. Structural basis of human ghrelin receptor signaling by ghrelin and the synthetic agonist ibutamoren. Nat Commun. 2021;12(1):6410. doi:10.1038/s41467-021-26735-5 PMID 34737341
- Misuse of Drugs Act 1971, Schedule 2. legislation.gov.uk (checked 2 October 2026).
- Human Medicines Regulations 2012, regulations 2 and 46. legislation.gov.uk.
- Psychoactive Substances Act 2016, section 2. legislation.gov.uk.
- MHRA. MHRA review shows sports supplement industry improvement. GOV.UK, 3 August 2016.
- UK Anti-Doping. What's banned in sport: the Prohibited List.