{"title":"Andarine (S-4)","description":"\u003cp\u003eAndarine, also known as S-4, S4, GTx-007 and by its chemical name S-3-(4-acetylamino-phenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethyl-phenyl)-propionamide, is a non-steroidal selective androgen receptor modulator (SARM) of the aryl-propionamide family. It was one of the first SARMs to be characterised in detail in animals but never reached later-stage human trials. This page lists every brand of andarine stocked at Free Muscle, compared on strength per capsule, capsules per pack and batch testing, and summarises the published research and its limits.\u003c\/p\u003e\n\u003ch2\u003eWhat is andarine?\u003c\/h2\u003e\n\u003cp\u003eAndarine is a synthetic ligand of the androgen receptor (AR) built on the aryl-propionamide scaffold that also produced ostarine and S-23. The scaffold was derived from the anti-androgen bicalutamide by researchers at the University of Tennessee and Ohio State University, who found that small structural changes turned a receptor blocker into a tissue-selective agonist. Andarine behaves as a partial agonist in the prostate and a full agonist in skeletal muscle and bone in animal models, which is the defining SARM profile.\u003c\/p\u003e\n\u003cp\u003eUnlike ostarine, andarine did not progress far in clinical development. GTx investigated it as GTx-007 for benign prostatic hyperplasia and muscle wasting in the mid-2000s, but no controlled human trial results have been published in the peer-reviewed literature and the compound was set aside in favour of ostarine. Andarine has never been approved as a medicine by the MHRA, EMA, FDA or any other regulator. It is widely discussed for a visual side effect, a yellow tint to vision and difficulty adapting to darkness, attributed to its nitro group, but this is reported anecdotally rather than in published trials.\u003c\/p\u003e\n\u003ch2\u003eWhat the published research reports\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eMuscle, bone and pituitary effects in castrated rats (2005).\u003c\/strong\u003e Gao and colleagues treated castrated male rats with S-4, dihydrotestosterone (DHT) or vehicle for eight weeks. S-4 restored soleus muscle mass and strength and levator ani muscle mass to the levels seen in intact animals, matching DHT. Where DHT more than doubled prostate and seminal vesicle weights relative to intact controls, S-4 returned them to only 16 and 17 per cent of control. S-4 also increased total body bone mineral density more than DHT and suppressed plasma LH and FSH in a dose-dependent manner, indicating agonist activity in the pituitary.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBone loss and body fat in ovariectomised rats (2007).\u003c\/strong\u003e Kearbey and colleagues treated 120 female rats for 120 days after ovariectomy. S-4 maintained whole-body and trabecular bone mineral density and cortical content, increased femoral bone strength on biomechanical testing and reduced body fat, in a model of accelerated bone loss.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePharmacokinetics in rats (2004).\u003c\/strong\u003e Kearbey and colleagues gave S-4 intravenously and orally to male rats across a range of doses. Clearance was slow, the half-life was between 2.6 and 5.3 hours, and oral bioavailability was complete at the lower doses and dose-dependent above that.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eUK market analysis of SARM products (2021).\u003c\/strong\u003e Leaney and colleagues, working in a UK laboratory, analysed supplement products marketed as SARMs to UK consumers. Findings ranged from products with no active ingredient to products containing undeclared prohibited substances, and where a SARM was present its concentration frequently did not match the label.\u003c\/p\u003e\n\u003cp\u003eAll of the andarine efficacy data above come from rats. There are no published controlled human trials, and none of these findings is a claim about the products listed on this page.\u003c\/p\u003e\n\u003ch2\u003eBrands of andarine we stock\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eiMuscle Andarine S-4, 15mg, 60 capsules.\u003c\/strong\u003e Capsule form, 900mg of compound per pack. A certificate of analysis is shown on the listing only where iMuscle has supplied one for the batch we hold; if none is displayed, none is available for that batch. \u003ca href=\"\/products\/imuscle-andarine-s4-60-15mg\"\u003eView the iMuscle Andarine listing\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFree Muscle does not currently produce its own andarine, so there is no Janoshik-assayed Free Muscle batch on this page at present. Any Free Muscle-brand line added later will carry batch-level Janoshik testing like the rest of our range.\u003c\/p\u003e\n\u003ch3\u003eHow to compare them\u003c\/h3\u003e\n\u003cp\u003eMultiply strength per capsule by capsules per pack to get total milligrams (15mg by 60 gives 900mg). Divide the pack price by that figure for cost per milligram, which is how a 15mg pack is compared fairly against a 25mg or 50mg pack from another supplier. Then weigh the certificate. Market analyses of SARM products, including the 2021 UK study above, have repeatedly found labels that do not match contents, so a batch-specific COA from an independent laboratory is the only way to know what a pack contains. Our guide to \u003ca href=\"\/blogs\/news\/price-per-mg-compare-sarms-peptides\"\u003eprice per milligram\u003c\/a\u003e covers the arithmetic.\u003c\/p\u003e\n\u003ch2\u003eBatch testing and certificates of analysis\u003c\/h2\u003e\n\u003cp\u003eA certificate of analysis (COA) answers the two questions that matter about an andarine capsule: is the compound what the label says, and how much is present. A genuine batch certificate is issued by an independent laboratory, names the lot number, and reports identity (by HPLC or mass spectrometry against a reference standard) and assayed purity or content.\u003c\/p\u003e\n\u003cp\u003eEvery Free Muscle-brand batch is assayed by Janoshik Analytical, an independent laboratory, and the certificate for the batch you receive is sent on request by email. For other brands we show a COA only where the manufacturer has supplied one for the batch we hold. A generic PDF with no batch number, or one dated long before the product was made, is not a batch certificate and tells you nothing about the capsules in your hand. Our \u003ca href=\"\/pages\/lab-tests\"\u003elab tests page\u003c\/a\u003e explains how to read a Janoshik certificate and match it to your batch.\u003c\/p\u003e\n\u003ch2\u003eLegal status in the UK\u003c\/h2\u003e\n\u003cp\u003eAndarine is not a licensed medicine in the United Kingdom. It has never been granted a marketing authorisation by the MHRA, and it is not an authorised food supplement or a permitted novel food ingredient. It cannot legally be sold or labelled for human consumption. Free Muscle sells andarine to adults aged 18 or over for laboratory and research purposes only, and every listing states this. Andarine is named on the World Anti-Doping Agency Prohibited List under S1.2, Other Anabolic Agents, and is prohibited at all times. Anyone subject to anti-doping rules should treat any product in this class as prohibited at all times, in and out of competition. For a fuller overview of the class, see our \u003ca href=\"\/blogs\/news\/what-are-sarms-the-2026-research-guide\"\u003eresearch guide to SARMs\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch2\u003eStorage and handling\u003c\/h2\u003e\n\u003cp\u003eKeep andarine capsules in the original sealed container in a cool, dry place away from light and heat. Do not decant into unlabelled containers, and record the batch number so that a COA request can be matched to the exact material. Keep out of reach of children and pets, and follow standard laboratory good practice: gloves when handling, no eating or drinking in the work area, and disposal in line with local rules for research chemicals.\u003c\/p\u003e\n\u003ch2\u003eDelivery and returns\u003c\/h2\u003e\n\u003cp\u003eOrders are sent by FreeMuscle LTD, a UK company in Scunthorpe, with free tracked delivery to UK addresses and plain packaging. Same-working-day processing applies to orders placed before 2pm, Monday to Friday, and EU delivery takes 3 to 7 working days. Unopened items are returnable within 30 days. We sell only to customers aged 18 or over. Details are on the \u003ca href=\"\/pages\/shipping\"\u003eshipping page\u003c\/a\u003e and the \u003ca href=\"\/pages\/guarantee\"\u003eguarantee page\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch2\u003eRelated reading\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-are-sarms-the-2026-research-guide\"\u003eWhat are SARMs? The 2026 research guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/sarms-explained-how-selective-androgen-receptor-modulators-work-1135-86\"\u003eSARMs explained: how selective androgen receptor modulators work\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-read-a-certificate-of-analysis\"\u003eHow to read a certificate of analysis\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/price-per-mg-compare-sarms-peptides\"\u003ePrice per milligram: the only honest way to compare SARMs and peptides\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eRelated collections: \u003ca href=\"\/collections\/ostarine\"\u003eOstarine (MK-2866)\u003c\/a\u003e, \u003ca href=\"\/collections\/s-23\"\u003eS-23\u003c\/a\u003e, \u003ca href=\"\/collections\/brand-imuscle\"\u003eiMuscle\u003c\/a\u003e, \u003ca href=\"\/collections\/sarms\"\u003eall SARMs\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eAndarine is sold strictly for laboratory research use only. It is not a licensed medicine, has not been evaluated or approved by the MHRA, EMA or FDA, is not a food supplement and is not for human consumption. Buyers must be 18 or over. Nothing on this page is medical advice, dosing advice or a recommendation to use this compound in any way; the published findings summarised above describe study participants and laboratory models, not the products listed.\u003c\/em\u003e\u003c\/p\u003e","products":[{"product_id":"imuscle-andarine-s4-60-15mg","title":"iMuscle Andarine S-4 — 60 caps, 15mg","description":"\u003cp\u003eiMuscle Andarine S-4 is supplied as 60 capsules stated at 15 mg each, for a total of 900 mg of andarine per pack. Andarine (S-4) is an early non-steroidal selective androgen receptor modulator whose published evidence comes from animal studies. The product is manufactured by iMuscle and stocked by Free Muscle for laboratory research by adults, with free tracked UK delivery.\u003c\/p\u003e\u003ch2\u003eAbout Andarine (S-4)\u003c\/h2\u003e\u003cp\u003eAndarine, usually written S-4 or S4 and coded GTx-007 during development, is one of the earliest non-steroidal selective androgen receptor modulators. It came from the aryl-propionamide series developed at the University of Tennessee and GTx Inc. in the early 2000s. Like testosterone, it binds and activates the androgen receptor. The series aimed at action on muscle and bone with less effect on other androgen-sensitive tissue; for andarine, that aim was tested only in animals.\u003c\/p\u003e\u003cp\u003eThe published data for S-4 are preclinical. In a 2007 study of 120 female rats, ovariectomised to model accelerated bone loss and treated for 120 days, S-4 maintained whole-body and trabecular bone mineral density and cortical bone content, increased the strength of the femur on mechanical testing and reduced body fat (Kearbey et al., 2007). No controlled human trial of andarine has been published, and the development programme was discontinued. In informal reports the most frequently described effect is a yellow tint to vision and slower adaptation to darkness, attributed in those accounts to the molecule binding in the retina; that finding has not been characterised in a clinical study.\u003c\/p\u003e\u003cp\u003eAndarine has never been approved as a medicine and is named under section S1.2 of the WADA Prohibited List. The animal findings summarised here are not claims about this product.\u003c\/p\u003e\u003ch3\u003eChemical identity\u003c\/h3\u003e\u003cp\u003eThese PubChem identifiers define the substance a certificate for this pack should report. The (2S) marks the molecule's single stereocentre.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSystematic name\u003c\/strong\u003e: (2S)-3-(4-acetamidophenoxy)-2-hydroxy-2-methyl-N-[4-nitro-3-(trifluoromethyl)phenyl]propanamide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCAS number\u003c\/strong\u003e: 401900-40-1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFormula and molecular weight\u003c\/strong\u003e: C19H18F3N3O6, 441.4 g\/mol\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInChIKey\u003c\/strong\u003e: YVXVTLGIDOACBJ-SFHVURJKSA-N\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePubChem CID\u003c\/strong\u003e: 9824562\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eThis listing\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eCompound: Andarine (S-4)\u003c\/li\u003e\n\u003cli\u003eBrand: iMuscle\u003c\/li\u003e\n\u003cli\u003eForm: capsules\u003c\/li\u003e\n\u003cli\u003ePack size: 60 capsules\u003c\/li\u003e\n\u003cli\u003eStated strength: 15 mg per capsule (manufacturer's label claim)\u003c\/li\u003e\n\u003cli\u003eStated total per pack: 900 mg\u003c\/li\u003e\n\u003cli\u003eIntended use: laboratory research only, not for human consumption\u003c\/li\u003e\n\u003cli\u003eSold to adults aged 18 and over\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eThe strength is the manufacturer's label claim; only a batch certificate confirms it. To compare brands of Andarine, use total milligrams per pack, as explained in \u003ca href=\"\/blogs\/news\/price-per-mg-compare-sarms-peptides\"\u003eprice per milligram\u003c\/a\u003e.\u003c\/p\u003e\u003ch2\u003eAndarine in the UK: buying, legal status and what to check\u003c\/h2\u003e\u003cp\u003eBehind searches such as \"andarine UK\", \"S4 SARM UK\" and \"S4 SARM for sale\" sit two questions: can andarine lawfully be bought here, and what makes a listing checkable rather than something taken on trust.\u003c\/p\u003e\u003ch3\u003eThe legal position\u003c\/h3\u003e\u003cp\u003eAndarine is not a licensed medicine in the UK: it has no MHRA marketing authorisation, is not an authorised food supplement, and cannot lawfully be sold for human consumption. Nor is it a controlled drug under the Misuse of Drugs Act 1971. Free Muscle supplies it to adults aged 18 or over for laboratory research only. It is prohibited at all times under section S1 (anabolic agents) of the WADA Prohibited List. Buyers are responsible for the rules that apply to them, including any anti-doping code and, for orders sent to the EU, their own country's import rules. Background on the class is in \u003ca href=\"\/blogs\/news\/what-are-sarms-the-2026-research-guide\"\u003eWhat are SARMs? The 2026 research guide\u003c\/a\u003e.\u003c\/p\u003e\u003ch3\u003eWhat a checkable listing shows, and how this one measures up\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eCheck\u003c\/th\u003e\n\u003cth\u003eThis listing\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eStrength, count and pack total that agree\u003c\/td\u003e\n\u003ctd\u003e15 mg per capsule, 60 capsules, 900 mg per pack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer and seller identified\u003c\/td\u003e\n\u003ctd\u003eMade by iMuscle; sold and dispatched by FreeMuscle LTD, a UK company in Scunthorpe\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCertificate tied to a lot number\u003c\/td\u003e\n\u003ctd\u003eThe manufacturer's COA, where iMuscle supplies one for the batch held (see the certificate section)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTerms of sale\u003c\/td\u003e\n\u003ctd\u003eLaboratory research only, adults aged 18 or over, no instructions for use, no before-and-after images or claims about results\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDelivery\u003c\/td\u003e\n\u003ctd\u003eFree tracked UK delivery in plain packaging; same-working-day processing for orders before 2pm Monday to Friday; EU delivery in 3-7 working days\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReturns\u003c\/td\u003e\n\u003ctd\u003eUnopened items within 30 days; see \u003ca href=\"\/pages\/shipping\"\u003edelivery\u003c\/a\u003e and \u003ca href=\"\/pages\/guarantee\"\u003eguarantee\u003c\/a\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003eA listing without an amount per capsule fails the first check: it can be neither priced per milligram nor compared with an assay.\u003c\/p\u003e\u003cp\u003eThis matters for andarine in particular. In 2009 anti-doping researchers at the German Sport University Cologne found andarine in oily liquids sold online as green tea extract and face moisturiser, and described the case as the first proof that SARMs were being sold and misused without any clinical approval (Thevis et al., 2009). Only analysis revealed what those bottles held; reviews and Reddit threads about \"S4\" record experiences, not contents. More checks are in \u003ca href=\"\/blogs\/news\/how-to-choose-a-sarms-supplier-uk-checklist\"\u003ehow to choose a SARMs supplier in the UK\u003c\/a\u003e.\u003c\/p\u003e\u003ch2\u003eCapsules compared with other forms\u003c\/h2\u003e\u003cp\u003eThree formats are sold under the andarine name: capsules, liquids and loose powder. Chemically they are identical; they differ in where the quantity per unit gets fixed and in how anyone can verify it. We know of no published comparison of andarine formats.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCapsules (this product).\u003c\/strong\u003e Powder is blended and filled into shells at manufacture, so the 15 mg per capsule is set before the pot is sealed and a certificate can measure it directly. The limit is uniformity: an assay of pooled capsules reports their average, and variation between capsules shows only if units are tested one by one.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLiquids.\u003c\/strong\u003e Labelled by concentration, so any portion is only as accurate as the volume measured. Solvent evaporating from a bottle opened repeatedly concentrates what remains, and a dissolved compound can come out of solution in the cold, so a certificate describes the liquid only as it was when sampled.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoose powder.\u003c\/strong\u003e Sold by weight, which places accuracy entirely on the balance and handling of the laboratory using it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInjection.\u003c\/strong\u003e Sometimes asked about by analogy with peptides. Andarine is a small synthetic molecule, not a peptide, so the objection raised against swallowed peptides, breakdown by digestive enzymes, does not apply in the same way (see \u003ca href=\"\/blogs\/news\/do-oral-peptides-work\"\u003edo oral peptides work\u003c\/a\u003e). No published human study has given andarine by injection or any other route.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eOn stability, dry powder sealed in a capsule is kept away from the solvents and water in which chemical breakdown usually proceeds fastest. That is a general principle, not a measured result: we know of no published shelf-life data for andarine in any format.\u003c\/p\u003e\u003ch2\u003eAndarine compared with ostarine\u003c\/h2\u003e\u003cp\u003e\"Andarine vs ostarine\" is the comparison searched most often for this compound, and the two are close relatives: aryl-propionamide SARMs from the same GTx programme, built on the same (2S)-2-hydroxy-2-methylpropanamide backbone with a trifluoromethyl group on the anilide ring. They differ in two substituents, and in how far each went in development.\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth\u003eAndarine (this product)\u003c\/th\u003e\n\u003cth\u003eOstarine\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOther names\u003c\/td\u003e\n\u003ctd\u003eS-4, S4, GTx-007\u003c\/td\u003e\n\u003ctd\u003eMK-2866, enobosarm, GTx-024\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGroup on the anilide ring\u003c\/td\u003e\n\u003ctd\u003eNitro\u003c\/td\u003e\n\u003ctd\u003eCyano\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGroup on the phenoxy ring\u003c\/td\u003e\n\u003ctd\u003eAcetamido\u003c\/td\u003e\n\u003ctd\u003eCyano\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFormula, molecular weight, CAS\u003c\/td\u003e\n\u003ctd\u003eC19H18F3N3O6, 441.4, 401900-40-1\u003c\/td\u003e\n\u003ctd\u003eC19H14F3N3O3, 389.3, 841205-47-8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePublished evidence\u003c\/td\u003e\n\u003ctd\u003eRat studies only\u003c\/td\u003e\n\u003ctd\u003ePhase 2 trials in older adults and in people with cancer; phase 3 trials in cancer-related muscle wasting\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAdverse findings in people\u003c\/td\u003e\n\u003ctd\u003eNone from controlled studies; visual changes in informal reports\u003c\/td\u003e\n\u003ctd\u003eAdverse events recorded in monitored trials; named in published reports of liver injury outside them\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLicensed as a medicine\u003c\/td\u003e\n\u003ctd\u003eNowhere\u003c\/td\u003e\n\u003ctd\u003eNowhere\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWADA\u003c\/td\u003e\n\u003ctd\u003eS1.2, prohibited at all times\u003c\/td\u003e\n\u003ctd\u003eS1.2, prohibited at all times\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003eThe real difference is depth of evidence. Ostarine's trials enrolled people under medical supervision and published what they measured, adverse events included; that record and its limits are set out in \u003ca href=\"\/blogs\/news\/ostarine-mk-2866-research-guide\"\u003eOstarine (MK-2866): the most-studied SARM, what trials found\u003c\/a\u003e. Andarine has no equivalent, so claims that it is \"stronger\" or \"milder\" than ostarine in people rest on anecdote. Milligrams do not translate either: andarine is the heavier molecule, so equal figures on two labels are not equal amounts of substance, and no study establishes any equivalence between them.\u003c\/p\u003e\u003cp\u003eIn law and in sport there is no difference, and both are sold here for laboratory research only. Ostarine brands, including \u003ca href=\"\/products\/imuscle-ostarine-k2866-60-15mg\"\u003eiMuscle Ostarine\u003c\/a\u003e, are compared in the \u003ca href=\"\/collections\/ostarine\"\u003eOstarine (MK-2866) collection\u003c\/a\u003e.\u003c\/p\u003e\u003ch2\u003eReading the certificate of analysis for this product\u003c\/h2\u003e\u003cp\u003eiMuscle is a third-party brand, so any certificate of analysis (COA) for this pack is the manufacturer's, not ours. Where iMuscle supplies a COA for the batch we hold, we show it; where none exists for the batch in stock, we say so rather than show a generic document. Free Muscle-brand compounds are assayed batch by batch at Janoshik Analytical; that programme does not cover iMuscle. A real andarine batch certificate should answer each point below.\u003c\/p\u003e\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhich compound.\u003c\/strong\u003e Andarine, S-4 or GTx-007, ideally with CAS 401900-40-1. A document headed only \"SARM\" says nothing about this pot.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIdentity, and by what method.\u003c\/strong\u003e HPLC matches the sample's retention time to a reference standard; LC-MS adds a molecular mass that should fit C19H18F3N3O6 (441.4 g\/mol). The 2009 Cologne analysis confirmed identity against reference material by both liquid chromatography and high-resolution mass spectrometry (Thevis et al., 2009).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePurity.\u003c\/strong\u003e Usually an HPLC area percentage: the share of detected material that is andarine. It is the line that would expose a by-product like the one in that 2009 sample, left by poor purification at roughly a tenth of the andarine present. It says nothing about milligrams per capsule.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eContent per capsule.\u003c\/strong\u003e The assayed milligrams in a capsule, the figure that tests the 15 mg claim. If it is missing, so is any check on the 900 mg total.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStereochemistry.\u003c\/strong\u003e Andarine is the (2S) form. Its (2R) mirror image has the same formula and mass and is not separated by standard HPLC; only a chiral method tells them apart. A certificate silent on this has not tested for it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLot number, test date and laboratory.\u003c\/strong\u003e The lot on the report has to be the lot on your pot; the test date tells you how old the result is; and the issuing laboratory, if named, can be asked whether the report is genuine.\u003c\/li\u003e\n\u003c\/ol\u003e\u003cp\u003eAny blank line means the matching label figure is still unverified; \u003ca href=\"\/pages\/contact\"\u003econtact us\u003c\/a\u003e and we will tell you what documentation exists for the stock we hold. See also \u003ca href=\"\/blogs\/news\/how-to-read-a-certificate-of-analysis\"\u003ehow to read a COA\u003c\/a\u003e and our \u003ca href=\"\/pages\/lab-tests\"\u003elab tests\u003c\/a\u003e page.\u003c\/p\u003e\u003ch2\u003eDetection, sport and testing\u003c\/h2\u003e\u003cp\u003eAndarine is named in section S1.2 (other anabolic agents) of the WADA Prohibited List and is banned in and out of competition; WADA has prohibited SARMs as a class since 2008 (Thevis et al., 2010). Anti-doping rules apply strict liability: an athlete is responsible for any prohibited substance in their sample, whatever its source, a mislabelled product included.\u003c\/p\u003e\u003cp\u003eTesting does not depend on finding the unchanged molecule. The same Cologne group then characterised andarine's urinary metabolites by liquid chromatography with high-resolution mass spectrometry and confirmed targets for routine doping control: glucuronic acid conjugates of andarine and of its hydroxylated or deacetylated products, a hydrolysis product formed when one of its two aromatic rings is removed, and sulfate conjugates of the hydroxylated and deacetylated metabolites (Thevis et al., 2010).\u003c\/p\u003e\u003cp\u003eWhat the published record does not give is a detection window. We know of no verified study reporting how long andarine or its metabolites remain detectable, so for this product the accurate statement is: detectable, window not established. The absence of a figure is not evidence of a short window. Anyone subject to anti-doping rules should treat any contact with andarine as a risk of an adverse analytical finding.\u003c\/p\u003e\u003ch2\u003eStorage, stability and handling\u003c\/h2\u003e\u003cp\u003eWe know of no published stability study of andarine capsules, so the expiry or best-before date printed by iMuscle is the working limit, and a certificate describes the batch as it was on its test date, not as it is now.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eContainer.\u003c\/strong\u003e Leave the capsules in the pot they came in and close it after every opening. Separated from that pot and its lot number, capsules can no longer be matched to a certificate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConditions.\u003c\/strong\u003e A cool, dry cupboard away from direct light and from radiators, ovens and sunny windowsills. Steam from bathrooms and kitchens softens capsule shells and makes powder clump.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecords.\u003c\/strong\u003e Write the opening date next to the lot number. Any portion taken for analysis needs its own label giving compound, lot and date.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChanges in appearance.\u003c\/strong\u003e Capsules that have discoloured, softened or stuck together are no longer the material a certificate describes; set them aside and \u003ca href=\"\/pages\/contact\"\u003econtact us\u003c\/a\u003e with the lot number.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHandling and disposal.\u003c\/strong\u003e Wear gloves for opened capsules or powder, work away from food and drink, keep the pot out of reach of children and pets, and dispose of unwanted material as chemical waste under local rules, never in household bins or drains.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eGlossary\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSARM\u003c\/strong\u003e: selective androgen receptor modulator; a non-steroidal ligand of the androgen receptor, pursued in the hope of anabolic action in muscle and bone with less action on the prostate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAndrogen receptor\u003c\/strong\u003e: the protein inside cells that testosterone and dihydrotestosterone activate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAryl-propionamide\u003c\/strong\u003e: the chemical family of andarine, ostarine and S-23, in which a propanamide chain links two substituted benzene rings.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePreclinical\u003c\/strong\u003e: research in cells or animals, before or instead of trials in people.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOvariectomised rat\u003c\/strong\u003e: a female rat with the ovaries removed, a standard model of bone loss after oestrogen deficiency.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBone mineral density\u003c\/strong\u003e: mineral content of bone per unit of area or volume, measured in the 2007 study by dual-energy X-ray absorptiometry.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnantiomers\u003c\/strong\u003e: two mirror-image forms of a molecule with a stereocentre, such as (2S)- and (2R)-andarine.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHPLC\u003c\/strong\u003e: high-performance liquid chromatography, which separates a sample's components for identification and measurement against a standard.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLC-MS\u003c\/strong\u003e: liquid chromatography coupled to mass spectrometry, adding each component's mass for a stronger identity check.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMetabolite\u003c\/strong\u003e: a breakdown or conversion product formed in the body; some persist longer than the parent molecule, which is why testers look for them.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGlucuronide\u003c\/strong\u003e: a metabolite formed when the body attaches glucuronic acid to a molecule, easing its excretion in urine.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRelated\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/collections\/andarine\"\u003eAll brands of Andarine (S-4)\u003c\/a\u003e, compared on strength, pack size and batch testing\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/collections\/brand-imuscle\"\u003eAll iMuscle products\u003c\/a\u003e stocked at Free Muscle\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/collections\/ostarine\"\u003eOstarine (MK-2866)\u003c\/a\u003e, \u003ca href=\"\/collections\/s-23\"\u003eS-23\u003c\/a\u003e and \u003ca href=\"\/collections\/sarms\"\u003eall SARMs\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/pages\/shipping\"\u003eDelivery\u003c\/a\u003e and \u003ca href=\"\/pages\/guarantee\"\u003ereturns\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cem\u003eThis product is supplied for laboratory research use only. It is not a medicine, has not been evaluated by the MHRA, EMA or FDA, and is not for human consumption. Sold to adults aged 18 and over. Nothing on this page is medical, dosing or usage advice.\u003c\/em\u003e\u003c\/p\u003e\u003ch2\u003eReferences\u003c\/h2\u003e\u003col\u003e\n\u003cli\u003eKearbey JD, et al. Selective Androgen Receptor Modulator (SARM) treatment prevents bone loss and reduces body fat in ovariectomized rats. Pharm Res. 2007;24(2):328-35. PMID: 17063395.\u003c\/li\u003e\n\u003cli\u003eThevis M, et al. Detection of the arylpropionamide-derived selective androgen receptor modulator (SARM) S-4 (Andarine) in a black-market product. Drug Test Anal. 2009;1(8):387-92. PMID: 20355219.\u003c\/li\u003e\n\u003cli\u003eThevis M, et al. Mass spectrometric characterization of urinary metabolites of the selective androgen receptor modulator andarine (S-4) for routine doping control purposes. Rapid Commun Mass Spectrom. 2010;24(15):2245-54. PMID: 20623476.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"iMuscle","offers":[{"title":"Default Title","offer_id":48468978893026,"sku":null,"price":39.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0772\/3499\/5426\/files\/ANDARINES4_720x_7a53b342-6ae9-441a-853c-b0481db9dbc3.jpg?v=1789931395"}],"url":"https:\/\/freemuscle.co.uk\/collections\/andarine.oembed","provider":"Free Muscle","version":"1.0","type":"link"}