GW501516 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-06-01. Numbers and descriptions here follow the published literature rather than marketing material.
Cardarine is a common name for the investigational chemical GW501516, also written GW-1516. It was developed as a peroxisome proliferator-activated receptor delta agonist for metabolic conditions such as dyslipidemia. Early research focused on lipid handling and energy use in skeletal muscle and other tissues. The compound was never approved as a medicine. In public discussion, it is often grouped with performance-enhancing substances, although its receptor target differs from that of anabolic steroids or selective androgen receptor modulators. Regulatory and health authorities have issued warnings about its use.
GW501516 acts on PPARδ, a nuclear receptor that helps regulate fatty acid oxidation and energy homeostasis. In animal studies, activation of this receptor was associated with increased endurance and changes in lipid metabolism. Human trials examined effects on blood lipids and other metabolic markers, but the compound did not advance to approval. Rodent studies later reported tumors in multiple tissues at doses used in those experiments. Whether those findings translate to human risk remains uncertain, and the clinical relevance of the animal data is still debated.
The pharmacological interest in cardarine centers on PPARδ activation and its downstream effects on lipid handling and mitochondrial function. In animal studies, PPARδ agonists have been associated with changes in exercise endurance and fatty acid utilization, though results vary by model and protocol. Human data remain sparse, and the absence of large controlled trials limits conclusions about efficacy. Researchers often describe the compound as a tool for probing PPARδ biology rather than a proven therapeutic agent.
Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.
Cardarine is a synthetic compound also known as GW501516, GW-501516, and sometimes endurobol. It was developed as a selective agonist of peroxisome proliferator-activated receptor delta, a nuclear receptor involved in fatty acid oxidation and energy metabolism. The compound was studied in preclinical models for metabolic and cardiovascular conditions, but it did not become a marketed human medicine. In regulatory and anti-doping contexts, it is treated as a prohibited substance rather than a licensed medicine.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Common internet and media name. |
| Research code | GW501516 | Also written GW-1516. |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator. |
| Development status | Discontinued | Clinical development halted after rodent cancer findings. |
| Regulatory status | Prohibited in sport | Listed by WADA; not approved as medicine. |
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
=== Pharmacokinetics === When administered parenterally (non-orally or non-rectally, e.g., intravenously or by injection), as is most common, naloxone has a rapid distribution throughout the body. The mean serum half-life has been shown to range from 30 to 81 minutes, shorter than the average half-life of some opiates, necessitating repeat dosing if opioid receptors must be stopped from triggering for an extended period. Naloxone is primarily metabolized by the liver. Its major metabolite is naloxone-3-glucuronide, which is excreted in the urine. For people with liver diseases such as alcoholic liver disease or hepatitis, naloxone usage has not been shown to increase serum liver enzyme levels. Naloxone has low systemic bioavailability when taken by mouth due to hepatic first-pass metabolism, but it does block opioid receptors that are located in the intestine.
Food and Drug Administration (FDA) was a Zydis ODT formation of Claritin (loratadine) in December 1996. It was followed by a Zydis ODT formulation of Klonopin (clonazepam) in December 1997, and a Zydis ODT formulation of Maxalt (rizatriptan) in June 1998. The regulatory condition for meeting the definition of an orally disintegrating tablet is USP method 701 for Disintegration. FDA guidance issued in Dec 2008 is that ODT drugs should disintegrate in less than 30 seconds. This practice is under review by the FDA as the fast disintegration time of ODTs makes the disintegration test too rigorous for some of the ODT formulations that are commercially available.
Traces of the drug were found on a mobile phone used by Mohamed Lahouaiej Bouhlel, a French-Tunisian who killed eighty-four civilians in Nice on Bastille Day in 2016. In May 2017, French customs at Charles de Gaulle Airport seized 750,000 fenethylline pills being transported from Lebanon to Saudi Arabia. In 2017, two other consignments of pills were found at Charles de Gaulle Airport: in January, heading for the Czech Republic, and in February, hidden in steel moulds. Further investigation showed that the seized products mainly contained a mixture of amphetamine and theophylline. In January 2018, Saudi Arabia seized 1.3 million fenethylline pills at the Al-Haditha crossing near the border with Jordan. In December 2018, Greece intercepted a Syrian ship sailing for Libya, carrying six tonnes of processed cannabis and three million fenethylline pills. In July 2019, a shipment of 33 million fenethylline pills, weighing 5.25 tonnes, was seized in Greece coming from Syria. In July 2019, 800,000 fenethylline pills were found on a boat in the United Arab Emirates. In August 2019, Saudi customs at Al-Haditha seized over 2.5 million fenethylline pills found inside a truck and a private vehicle. In February 2020, the UAE found 35 million fenethylline pills in a shipment of electric cables from Syria to Jebel Ali. In April 2020, Saudi Arabia seized 44.7 million fenethylline pills smuggled from Syria, and citing drug smuggling concerns, imposed an import ban on fruits and vegetables from Lebanon, causing the price of Lebanese lettuce to plummet.
== Prognosis == Venous ulcers are costly to treat, and there is a significant chance that they will recur after healing; one study found that up to 48% of venous ulcers had recurred by the fifth year after healing. However, treatment with local anaesthetic endovenous techniques suggests a reduction of this high recurrence rate is possible. Without proper care, the ulcer may get infected, leading to cellulitis or gangrene and eventually may need amputation of the part of the limb in the future. Some topical drugs used to treat venous ulcer may cause venous eczema.
Sources: en.wikipedia.org
2023 North Sea incident: Two cargo ships, the British-flagged Verity and the Bahamas-flagged Polesie, collide in the North Sea near the Heligoland islands, with several individuals missing and the suspected sinking of the Verity. 25 October Lloyds Banking Group releases forecasts for UK house prices, predicting they will shrink by 4.7% in 2023 and 2.4% in 2024, before beginning to rise again in 2025. Sunak tells Parliament he supports "specific pauses" in the Israel–Hamas conflict to allow the delivery of aid and get British citizens out of the area. Lewis Edwards, a former officer with South Wales Police who groomed 210 underage girls using social media and blackmailed them into sending him indecent photographs, is sentenced to life imprisonment with a minimum term of 12 years. Three members of the Just Stop Oil protest group are arrested on suspicion of criminal damage after spraying the Wellington Arch in central London with orange paint. A police misconduct hearing finds that two Metropolitan Police officers who stopped and searched athletes Bianca Williams and Ricardo Dos Santos in west London committed gross misconduct, and the officers are dismissed. 26 October – Sunak gives a speech warning of the dangers of artificial intelligence. 27 October Labour Mayor of London Sadiq Khan, Mayor of Greater Manchester Andy Burnham, and Scottish Labour leader Anas Sarwar break with the stance of Labour's leader, Sir Keir Starmer, on the Israel–Hamas conflict by calling for a ceasefire in Gaza.
=== High-throughput proteomic technologies === Proteomics has steadily gained momentum over the past decade with the evolution of several approaches. Few of these are new, and others build on traditional methods. Mass spectrometry-based methods, affinity proteomics, and micro arrays are the most common technologies for large-scale study of proteins.
== D == dalton – Darwinian fitness – Darwinism – decomposer – dehydrogenase – deletion – denaturation – dendrite – dengue – denitrification – deoxyribonucleic acid – deoxyribose – depolarization – desmosome – deuterostome – diabetes mellitus – diastole – diffusion – digestion – dihybrid cross – dikaryon – dikaryotic – disaccharide – DNA ligase – DNA methylation – DNA polymerase – double circulation – double helix – Down syndrome – drupe – duodenum – dynein
== History == The effect of grapefruit juice on drug absorption was discovered in 1989 by a group led by pharmacologist David Bailey. Their first published clinical report on grapefruit vs. drug interactions was in 1991. The effect was discovered accidentally in 1989, when a test of drug interactions with alcohol used grapefruit juice to hide the taste of the ethanol. A 2005 medical review advised patients to avoid all citrus juices until further research clarified the risks. It was reported in 2008 that similar effects had been observed with apple juice.
Protein folding is the physical process describing how a polypeptide chain folds into a stable biologically functioning 3D-structure known as the native state. It happens after the polypeptide is synthesized by the ribosome. In some cases this happens co-translationally, where the nascent chain begins to fold while the rest of the polypeptide is being synthesized. In other cases, chaperone proteins can assists the folding.
Sources: en.wikipedia.org
No. Cardarine is a PPARδ agonist, while selective androgen receptor modulators act on androgen receptors. The two classes differ in receptor target and downstream effects.
Preclinical rodent studies reported cancers, including liver and bladder tumors, at tested doses. The human relevance of those findings is uncertain, but development was discontinued. No approved human product resulted.
No. It remains an investigational compound without approved therapeutic labeling. Sports regulators prohibit its use, and health agencies have warned against consuming it.
Cardarine is an investigational synthetic compound that acts as a PPARδ agonist. It is also known as GW501516 and has been studied mainly in preclinical research. It is not an approved medicine.