SR9009 (Stenabolic) Capsules UK
1 product from 1 brand · free UK delivery · EU 3–7 days
Last reviewed · prices and listings checked by Free Muscle
SR9009, sold under the name Stenabolic and sometimes written SR-9009, is a synthetic small-molecule agonist of the nuclear receptors Rev-Erbα and Rev-Erbβ, which sit at the heart of the circadian clock and regulate genes for lipid and glucose metabolism. It is not a SARM, has never been studied in a human trial and is not an approved medicine anywhere. This page lists every brand of SR9009 stocked at Free Muscle, compared on strength per capsule, capsules per pack and batch testing.
What is SR9009?
SR9009 was designed at the Scripps Research Institute in Florida as a research tool for studying Rev-Erb, together with a sister compound, SR9011. Rev-Erb proteins are transcriptional repressors: when activated they switch off target genes, including core clock genes and genes involved in fat storage, gluconeogenesis and inflammation. In mice, activating Rev-Erb altered circadian behaviour and raised energy expenditure, which is the origin of the reputation the compound later acquired in the fitness market.
Two facts limit that reputation. First, the animal studies gave SR9009 by injection, and we found no study, searching PubMed in October 2026, that measured how much SR9009 reaches the blood when it is taken by mouth, so whether a capsule delivers meaningful amounts is unknown. Second, a 2019 study using mice with both Rev-Erb genes deleted found that SR9009 still changed cell viability and metabolism, so some of its effects are not mediated by Rev-Erb at all and its true mechanism is unresolved. There are no human trials, no human safety studies and no regulatory approval. The 2026 WADA Prohibited List names SR9009, with SR9011, as a Rev-Erbα agonist in section S4.4 (metabolic modulators), prohibited at all times.
Identifiers (PubChem CID 57394020, checked October 2026): CAS 1379686-30-2, formula C20H24ClN3O4S, molar mass 437.9 g/mol.
What the published research reports
The 2012 Nature paper that introduced SR9009 reported that injected SR9009 altered circadian gene expression in mice, increased energy expenditure and reduced fat mass and plasma lipids in diet-induced obese mice, without changing food intake (Solt 2012). A 2013 study in Nature Medicine reported that Rev-Erbα regulates mitochondrial content in skeletal muscle and that injected SR9009 increased running endurance in mice, alongside greater mitochondrial biogenesis (Woldt 2013). A 2016 in vitro study of SR9009 and SR9011 metabolism, carried out for anti-doping purposes, characterised the metabolites produced by liver enzymes so that laboratories could detect the compound in athletes (Geldof 2016). Then in 2019 a group at the University of Pennsylvania showed that SR9009 decreased cell viability and rewired metabolism in hepatocytes and embryonic stem cells that lacked both Rev-Erbα and Rev-Erbβ, concluding that its effects cannot be used as a proxy for Rev-Erb activity (Dierickx 2019).
Other findings are limiting. In mice, SR9009 changed sleep architecture, increasing wakefulness during the light period when mice normally rest (Amador 2016). Every efficacy result is from injected mice or cultured cells.
In people, two case reports describe liver injury after use: in 2025, hepatocellular injury in a 40-year-old man taking several supplements who had recently started a product sold as Stenabolic, and who improved after stopping it (Govil 2025); and in 2026, acute liver failure needing an emergency liver transplant in a 17-year-old, with viral, autoimmune, metabolic and obstructive causes excluded (Shams Bin Shaheen 2026). Case reports show an association in time, not proof of cause. None of the above is a claim about any product on this page.
- Solt LA, et al. Regulation of circadian behaviour and metabolism by synthetic REV-ERB agonists. Nature. 2012;485(7396):62-68. PMID: 22460951.
- Woldt E, et al. Rev-erb-α modulates skeletal muscle oxidative capacity by regulating mitochondrial biogenesis and autophagy. Nat Med. 2013;19(8):1039-1046. PMID: 23852339.
- Geldof L, et al. In Vitro Metabolic Studies of REV-ERB Agonists SR9009 and SR9011. Int J Mol Sci. 2016;17(10):1676. PMID: 27706103.
- Dierickx P, et al. SR9009 has REV-ERB-independent effects on cell proliferation and metabolism. Proc Natl Acad Sci U S A. 2019;116(25):12147-12152. PMID: 31127047.
- Amador A, et al. Pharmacological Targeting the REV-ERBs in Sleep/Wake Regulation. PLoS One. 2016;11(9):e0162452. PMID: 27603791.
- Van Wagoner RM, et al. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet. JAMA. 2017;318(20):2004-2010. PMID: 29183075.
- Govil D, et al. When Gains Go Wrong: A Case of Selective Androgen Receptor Modulator-Related Liver Injury. Cureus. 2025;17(7):e87376. PMID: 40765588.
- Shams Bin Shaheen S, et al. Acute Liver Failure in an Adolescent Following Use of the Synthetic REV-ERB Agonist SR9009. Case Reports Hepatol. 2026;2026:9926772. PMID: 42750938.
Brands of SR9009 we stock
- iMuscle Stenabolic SR-9009, 10mg, 60 capsules. iMuscle brand, capsule form, 10mg per capsule, 60 capsules, 600mg in the pack. The listing currently shows two iMuscle documents, both dated 2021: a test protocol giving an HPLC assay of 99.9 per cent and an HPLC report for lot 20210911 with a main peak of 99.0 per cent. Compare that lot number with the one on your pack; if they differ, the documents do not describe your batch. We show only what iMuscle supplies and do not imply a test that does not exist.
There is currently no Free Muscle-brand SR9009, so no listing on this page carries a Janoshik Analytical certificate. As further brands are added they will appear here with the same information: strength, count, form and batch documentation.
How to compare them
Strength per capsule multiplied by capsules per pack gives total compound: 60 capsules at 10mg is 600mg. Divide the price by that figure for cost per milligram. When a second brand is listed, compare on that number and on whether a batch-specific certificate exists, not on the label design or the name on the tub. The Stenabolic name is a marketing term and tells you nothing about what is in the capsule.
Batch testing and certificates of analysis
For SR9009, a certificate of analysis should show, by HPLC or LC-MS against an SR9009 reference standard, that the material is SR9009, and give the purity, the laboratory, the batch number and the test date. Identity matters here. An analysis of 44 products bought online as SARMs found another unapproved drug, SR9009 among them, in 39 per cent, unlisted substances in a quarter and the labelled amount in only 41 per cent (Van Wagoner 2017), and a doping-control laboratory found SR9009 in a black-market product (Geldof 2016).
For iMuscle, the only brand on this page, we show a certificate only when the manufacturer provides one for the batch in stock. Whatever its source, a PDF without a batch number, test date or named laboratory is not a batch certificate, and its batch number should match your pack. Our lab tests page explains what to look for.
Where to buy SR9009 in the UK: how to check a supplier
Whichever shop you buy SR9009 from, check these five points before you order:
- A batch number and a certificate for that batch. The pack should carry a batch number, and the seller should be able to show a certificate of analysis for that same batch from a named laboratory, with the test date. For iMuscle, a certificate is shown where the brand supplies one for the batch we hold.
- The strength per capsule and the capsule count. With both figures you can work out the total milligrams in the pack and the price per milligram. If a listing does not state one of them, ask the seller before you order.
- Research-use labelling and an age check. A research compound should be sold for laboratory research use only, not for human consumption, to adults aged 18 or over, with no dosing or usage advice. That is how every listing here is sold.
- Prices in pounds sterling and tracked UK dispatch. UK delivery from us is free and tracked on every order, with no minimum spend, and usually arrives 2-3 working days after dispatch; orders placed before 2pm Monday to Friday are processed the same working day.
- A clear returns policy. Unopened items can be returned to us within 30 days.
Brand on this page: iMuscle. The UK supplier checklist and how we test go into more detail.
Legal status in the UK
SR9009 holds no MHRA marketing authorisation, which means it is not licensed as a medicine in the UK. Nor does it hold any food supplement authorisation, so it may not be sold for people to consume. The Misuse of Drugs Act 1971 does not list it, and Free Muscle supplies it for laboratory research to adults only. In sport, the 2026 WADA Prohibited List names it in section S4.4, metabolic modulators, as a Rev-Erbα agonist, banned at all times. Our SARMs research guide explains how UK law treats research compounds.
Storage and handling
Store the sealed container somewhere cool, dry and dark, close it promptly after each opening, and keep the capsules in their labelled container with the batch number, out of reach of children and animals. Wear gloves and work on a clean surface when handling them, and send unwanted material to a chemical waste route rather than the sink.
Delivery and returns
Free Muscle is the trading name of FreeMuscle, a business registered in Andorra, with UK operations and dispatch in Scunthorpe. Orders to UK addresses go by free tracked delivery in plain packaging, an order placed before 2pm from Monday to Friday is processed that working day, and parcels for the EU take three to seven working days. Unopened items may be sent back within 30 days, and nobody under 18 may order. See the shipping page and the guarantee page for full terms.
Related reading
- SR9009 (Stenabolic): what the REV-ERB research shows
- Cardarine (GW-501516): why development stopped and what the data show
- What are SARMs? The 2026 research guide
- Price per milligram: the only honest way to compare
- How to read a certificate of analysis
- Cardarine (GW-501516), SLU-PP-332, metabolic support and all SARMs
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.
Research guides
Frequently asked questions
Is SR9009 legal in the UK?
SR9009 is legal to buy and hold for research purposes in the UK and is not a controlled drug. It is not, however, a licensed medicine or an authorised food supplement, so it cannot lawfully be sold for people to consume. Free Muscle supplies it for laboratory research to adults aged 18 and over only. In sport, the 2026 WADA Prohibited List names it in section S4.4 (metabolic modulators), and it is banned at all times.
Is SR9009 a SARM?
No. SR9009 is a Rev-Erb agonist, acting on nuclear receptors that form part of the circadian clock. A SARM by definition binds the androgen receptor, and SR9009 has no affinity for it. It is sold in the same shops and to the same buyers, which is why the confusion persists, but it belongs to a different pharmacological class.
Has SR9009 been tested in humans?
Not in any trial. There are no clinical trials of SR9009, no human safety studies and no regulatory approval anywhere. The human evidence is limited to two case reports, in 2025 and 2026, in which people developed liver injury after using products labelled SR9009 or Stenabolic, one of them acute liver failure that needed a transplant. Everything published about its intended effects comes from injected mice and cultured cells, and a 2019 study found that some effects occur even in cells with no Rev-Erb receptors.
What is known about the safety of SR9009?
No safety study in people exists, so its side-effect profile is unknown. Two case reports describe liver injury after use: a 40-year-old man in 2025 who improved after stopping a product sold as Stenabolic, and a 17-year-old in 2026 who developed acute liver failure and needed an emergency liver transplant. In mice, SR9009 increased wakefulness during the normal rest period, and a 2019 study showed effects that do not run through its intended target. Nothing published supports calling it harmless.
What is the difference between SR9009 and Cardarine?
They are unrelated molecules that happen to share a market. Cardarine is a PPARδ agonist with a small amount of short-term human trial data and a rodent carcinogenicity history that halted development. SR9009 is a Rev-Erb agonist that has never been tested in a human trial. Both are prohibited by WADA under section S4.4, metabolic modulators.
Does SR9009 affect testosterone?
There is no evidence either way. SR9009 is a Rev-Erb agonist, not an androgen receptor ligand, and our October 2026 PubMed search turned up no study that measured testosterone in animals or people given SR9009. The only related experiment we found used mouse testis cells in a dish, which cannot show what happens in a living organism. We make no claim about its effect on hormones.
Does SR9009 work orally?
No study measuring how much SR9009 reaches the blood after it is taken by mouth appears in PubMed (searched in October 2026), and the animal studies that produced its reputation gave it by injection. Whether a capsule delivers anything meaningful is therefore unknown. We make no claim about it, and SR9009 is supplied for laboratory research only.
Is SR9009 detectable in sport drug tests?
Yes. Section S4.4 of the 2026 WADA Prohibited List names SR9009. Anti-doping researchers have characterised the metabolites that human liver enzymes produce from SR9009 so that laboratories can screen for them, and certified reference materials of two human metabolites have been produced for doping-control laboratories. No published study gives a detection window. Athletes who are tested should assume it is prohibited.
How do I verify the batch of SR9009 I receive?
The SR9009 currently listed is made by iMuscle. A certificate is shown on the product page only where iMuscle supplies one; at present the listing shows two documents dated 2021, one of them an HPLC report for lot 20210911. Check that the lot or batch number on any certificate matches the number printed on your pack before relying on it.
Which SR9009 strength should I choose?
There is only one SR9009 listing at present, the iMuscle 10mg, 60-capsule pack, so no choice arises, and we would not make a recommendation if it did. SR9009 is supplied for laboratory research and nothing here is guidance on selection or use. The factual figure for the listing is 600mg of compound per pack, which is the number to use for any cost-per-milligram comparison when other brands appear.
Where can I buy SR9009 in the UK?
On this page you can compare every SR9009 listing we stock (at present from iMuscle). Every UK order ships free with tracking, with no minimum spend, and usually arrives 2-3 working days after dispatch. Everything here is supplied for laboratory research use only, not for human consumption, to adults aged 18 or over.
How fast is UK delivery?
UK delivery is free and tracked on every order, with no minimum spend, and usually arrives 2-3 working days after dispatch. Faster tracked UK delivery costs £6 and usually takes 1-2 working days. Orders placed before 2pm Monday to Friday are processed the same working day.
Do you deliver to Romania and the rest of the EU?
Yes. Orders to Romania and other EU countries travel by our paid, tracked international service and usually arrive 3-7 working days after dispatch; delivery to the rest of the world usually takes 5-14 working days. Prices are in pounds sterling (GBP). Rules differ in other countries, so check local law before ordering for delivery abroad.
Can I return an order?
Yes: unopened items can be returned within 30 days. Our guarantee page has the full policy.