Cardarine (GW-501516)
4 products from 3 brands · free UK delivery · EU 3–7 days
Every Cardarine (GW-501516) listing compared
Strength and pack size as stated by each manufacturer. Total milligrams = strength per capsule multiplied by capsules per pack. Price per milligram is calculated from the current price. A dash means the manufacturer does not state that figure.
| Brand | Listing | Strength | Pack | Total | Price | Per mg | Availability |
|---|---|---|---|---|---|---|---|
| FreeMuscle | Cardarine GW-501516 — 10mg · 60 Capsules | 10mg | 60 capsules | 600mg | £39.99 | £0.067 | In stock |
| FreeMuscle | Cardarine GW-501516 — 5mg · 60 Capsules | 5mg | 60 capsules | 300mg | £29.99 | £0.100 | In stock |
| Thoroughbred Labs | Cardarine GW-501516 | – | 60 capsules | – | £34.99 | – | In stock |
| iMuscle | Cardarine GW-501516 — 60 caps, 10mg | 10mg | 60 capsules | 600mg | £49.99 | £0.083 | In stock |
Cardarine, also known as GW-501516, GW501516, GW1516 and Endurobol, is a synthetic agonist of the peroxisome proliferator-activated receptor delta (PPARδ), a nuclear receptor that regulates fat oxidation in muscle. It is often sold alongside SARMs but is not one. Its clinical development was halted after long-term rodent studies found cancers at multiple sites. This page lists every brand of Cardarine stocked at Free Muscle and compares them on strength per capsule, capsules per pack and batch testing.
What is Cardarine?
GW-501516 was developed in the 1990s and 2000s by GlaxoSmithKline in collaboration with Ligand Pharmaceuticals as a potential treatment for dyslipidaemia and metabolic disease. It activates PPARδ, which switches on genes for fatty acid uptake and oxidation in skeletal muscle and changes the handling of HDL and triglyceride-rich lipoproteins. It is not a SARM: it does not bind the androgen receptor at all. The two are grouped together in this market only because they are sold to similar buyers.
The compound reached Phase 2 human trials and was then abandoned. The decisive finding was that two-year carcinogenicity studies in rats and mice reported tumours in several organs, including liver, bladder, stomach, skin, thyroid, tongue and testes, and development stopped in 2007. No regulator has ever approved it. WADA added GW-501516 to the Prohibited List in 2009 and in 2013 issued a public warning to athletes about its safety. It is now listed under S4 (hormone and metabolic modulators) as a PPARδ agonist.
What the published research reports
A 2007 study gave healthy volunteers GW-501516 or placebo for two weeks while they were hospitalised and sedentary. HDL cholesterol rose and serum fat clearance after a fat meal improved in the treated groups, with a two-fold rise in ABCA1 expression in muscle cells in vitro; the trial involved 24 people and lasted only a fortnight (Sprecher 2007). A 2008 two-week study in moderately obese men reported reductions in fasting triglycerides, apolipoprotein B, LDL cholesterol and liver fat, with six participants per group (Risérus 2008). In mice, a 2008 study reported that GW-501516 combined with exercise training increased running endurance and shifted muscle fibre gene expression, while the drug alone did not; the effect was in trained mice, not sedentary ones (Narkar 2008). A 2014 review of PPAR agonists records that development of GW-501516 had been abandoned because of safety issues (Sahebkar 2014). The human studies were tiny and short, and none addressed long-term safety. None of the above is a claim about any product on this page.
- Sprecher DL, et al. Triglyceride:high-density lipoprotein cholesterol effects in healthy subjects administered a peroxisome proliferator activated receptor delta agonist. Arterioscler Thromb Vasc Biol. 2007;27(2):359-365. PMID: 17110604.
- Risérus U, et al. Activation of peroxisome proliferator-activated receptor (PPAR)delta promotes reversal of multiple metabolic abnormalities, reduces oxidative stress, and increases fatty acid oxidation in moderately obese men. Diabetes. 2008;57(2):332-339. PMID: 18024853.
- Narkar VA, et al. AMPK and PPARdelta agonists are exercise mimetics. Cell. 2008;134(3):405-415. PMID: 18674809.
- Sahebkar A, Chew GT, Watts GF. New peroxisome proliferator-activated receptor agonists: potential treatments for atherogenic dyslipidemia and non-alcoholic fatty liver disease. Expert Opin Pharmacother. 2014;15(4):493-503. PMID: 24428677.
Brands of Cardarine we stock
- Free Muscle Cardarine GW-501516, 10mg, 60 capsules. Free Muscle brand, 10mg per capsule, 60 capsules, 600mg in the pack. Every batch is assayed by Janoshik Analytical and the certificate for your batch is sent on request.
- Free Muscle Cardarine GW-501516, 5mg, 60 capsules. Free Muscle brand, 5mg per capsule, 60 capsules, 300mg in the pack. Janoshik batch-tested, certificate on request.
- iMuscle Cardarine GW-501516, 10mg, 60 capsules. 10mg per capsule, 60 capsules, 600mg in the pack. A COA is shown where iMuscle supplies one for the batch we hold.
- Thoroughbred Labs Cardarine GW-501516. 60 capsules. No per-capsule strength is published by the manufacturer, so no total can be stated. A COA is shown where Thoroughbred Labs supplies one for the batch we hold.
How to compare them
Multiply strength per capsule by capsules per pack: 10mg by 60 is 600mg, 5mg by 60 is 300mg. Divide the price by total milligrams to get cost per milligram, and note that a lower strength is rarely proportionally cheaper. For the listing with no published strength, compare on documentation only. In every case, check that the batch number on the certificate matches the pack you receive.
Batch testing and certificates of analysis
A certificate of analysis (COA) is a laboratory report tied to one manufactured batch. It records the identity of the compound tested (usually by HPLC or LC-MS against a reference standard) and the purity found, and it carries the batch number, the test date and the name of the laboratory that ran the assay. Every Free Muscle-brand batch is assayed by Janoshik Analytical, an independent laboratory, and we will send the certificate for the batch you hold if you email us with the batch number from the label. For the other brands on this page (iMuscle and Thoroughbred Labs) a COA is shown only where the manufacturer has supplied one for the specific batch we hold, and we leave the field blank rather than imply a test that does not exist.
A generic PDF with no batch number, no date or no named laboratory is not a batch certificate, whatever it is called. Match the batch number on the certificate to the number on your pack before relying on it. Our lab tests page explains what to look for.
Legal status in the UK
Cardarine is not a licensed medicine in the UK and has no MHRA marketing authorisation. It is not an authorised food supplement and may not be sold for human consumption. It is supplied for laboratory research to adults aged 18 and over. It is not a controlled drug under the Misuse of Drugs Act. In sport it is prohibited at all times under WADA class S4, hormone and metabolic modulators, where it is named as GW1516. For context on how SARMs and related research compounds are treated in UK law, read our SARMs research guide.
Storage and handling
Keep the container sealed, in a cool, dry place away from direct light, and return it there each time the container has been opened. Do not decant into unlabelled containers. Keep out of the reach of children and animals. Handle in line with ordinary laboratory good practice, with gloves and a clean work surface, and dispose of unwanted material through an appropriate waste route rather than down the sink.
Delivery and returns
Free Muscle is a UK company (FreeMuscle LTD, Scunthorpe). Every order ships with free tracked UK delivery in plain packaging with nothing on the outside to say what is inside. Orders placed before 2pm Monday to Friday are processed the same working day. EU delivery takes three to seven working days. Unopened items can be returned within 30 days. Customers must be 18 or over. Full details are on our shipping page and our guarantee page.
Related reading
- What are SARMs? The 2026 research guide
- SARMs explained: how selective androgen receptor modulators work
- Price per milligram: the only honest way to compare
- How to read a certificate of analysis
- SR9009 (Stenabolic), all SARMs, metabolic support and SLU-PP-332
Cardarine (GW-501516) is supplied for laboratory research use only. It is not a licensed medicine, not a food supplement and not for human consumption. Nothing on this page has been evaluated by the MHRA, EMA or FDA, and nothing on this page is medical, health or dosing advice. Sales are restricted to adults aged 18 and over.
Frequently asked questions
Is Cardarine legal in the UK?
Purchase and possession for research are lawful in the UK, since GW-501516 is not a controlled drug. Selling it as a medicine or for human consumption is not, because it has no MHRA licence and is not an authorised food supplement. That is why it is supplied here solely for laboratory research to adults aged 18 and over. In sport it is prohibited at all times under WADA class S4 as a PPARδ agonist.
Is Cardarine a SARM?
No. Cardarine (GW-501516) is a PPARδ agonist, acting on a nuclear receptor that regulates fat oxidation. It does not bind the androgen receptor, which is what defines a SARM. It is sold alongside SARMs because it reaches the same buyers, but pharmacologically it belongs to a different class altogether.
Why was Cardarine development stopped?
Development was halted in 2007 after two-year carcinogenicity studies in rats and mice reported tumours at multiple sites across several organ systems. The compound had reached Phase 2 human trials. No regulator has approved it, and WADA issued a public safety warning about it to athletes in 2013.
What is the difference between Cardarine and SR9009?
The two are often confused because they are sold to the same buyers, but they act on different receptors. Cardarine is a PPARδ agonist with a small amount of short human trial data. SR9009 is a Rev-Erb agonist with no human trials at all. Both are on the WADA Prohibited List under S4, hormone and metabolic modulators.
Is Cardarine detectable in sport drug tests?
Yes. Anti-doping laboratories have detected GW-501516 and its metabolites in athlete samples since it joined the Prohibited List in 2009, and there have been numerous sanctions in cycling and other sports. For anyone competing under anti-doping rules, detection should be treated as a certainty rather than a risk.
How do I verify the batch of Cardarine I receive?
It depends on the brand. Both Free Muscle Cardarine strengths are tested at Janoshik Analytical, and the certificate for your specific batch is sent by email when you quote the batch number from the label. iMuscle and Thoroughbred Labs Cardarine show a manufacturer's certificate on the listing only if one exists for the batch we hold. Whatever the source, read the batch number, purity figure and laboratory name on the document and compare them with your pack.
Should I choose 5mg or 10mg Cardarine?
We do not recommend one strength over another, because Cardarine is supplied for laboratory research and we do not advise on selection or use. What we can state is arithmetic: 60 capsules at 10mg contain 600mg of compound and 60 capsules at 5mg contain 300mg, so cost per milligram follows from the price of each pack. Both Free Muscle strengths are Janoshik batch-tested.
How is Cardarine shipped and can I return it?
Delivery within the UK is tracked and free on every order, in plain packaging. Orders received before 2pm on a weekday are processed the same working day. For EU addresses allow three to seven working days. Unopened items can be returned within 30 days; once a pack has been opened it cannot be returned. Sales are to adults aged 18 and over only.