A practical reference on Research chemical: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport; not approved as medicine | Listed by WADA at all times. |
| Common synonyms | GW501516, GW-501516, endurobol | Cardarine is a colloquial name. |
| Typical analytical method | LC-MS/MS | Detects parent compound and metabolites. |
| Common test matrix | Urine | Blood and dried blood spots also possible. |
| Legal classification | Varies by country | Often treated as unapproved drug or research chemical. |
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.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
Handling and quality assessment of cardarine reference material follow general laboratory practices for poorly characterized compounds. It typically appears as a white to off-white powder and is sparingly soluble in water but soluble in organic solvents such as dimethyl sulfoxide and ethanol. Storage recommendations usually specify a cool, dry, dark place, with long-term storage at low temperature and desiccation. Purity may be checked by high-performance liquid chromatography with ultraviolet detection, while identity is confirmed by mass spectrometry and nuclear magnetic resonance. No pharmacopeial monograph exists, so reported purity and stability depend on the supplier’s methods.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
== Overview of AIDA physiological model == AIDA has been described in detail in the medical / scientific / computing / diabetes literature. It incorporates a compartmental model that describes glucose-insulin interaction in people completely lacking endogenous insulin secretion — i.e. insulin-dependent patients with type 1 diabetes mellitus. The AIDA model contains a single extra-cellular glucose compartment into which glucose enters via both absorption from the intestine and glucose production from the liver. The model also contains separate compartments for plasma and 'active' insulin, the latter being responsible for glycemic control while insulin is removed from the former by liver degradation. Full details of the AIDA model are accessible from within the AIDA software package, and can be viewed and printed separately via the AIDA website.
=== La–Li === Irving Langmuir (1881–1957), American chemist, physicist, 1932 Nobel Prize in Chemistry for work in surface chemistry Auguste Laurent (1807–1853), French chemist who discovered trichloroethylene, anthracene, phthalic acid, and carbolic acid Paul Lauterbur (1929–2007), American chemist, Nobel Prize in Physiology or Medicine (2003) work which that the development of magnetic resonance imaging possible Antoine Lavoisier (1743–1794), French chemist who recognized oxygen and hydrogen as elements Nicolas Leblanc (1742–1806), French chemist and surgeon who discovered how to manufacture soda ash from common salt Henri Louis Le Chatelier (1850–1936), French chemist known for Le Chatelier's principle, which allows prediction of the effect of a changing condition on a system in chemical equilibrium Yuan T. Lee (born 1936), Taiwanese chemist, 1986 Nobel Prize in Chemistry for contributions to the development of reaction dynamics Valery Legasov (1936–1988), Soviet inorganic chemist known for his position as head of the Chernobyl Commission for the Chernobyl Disaster Jean-Marie Lehn (born 1939), French chemist, 1987 Nobel Prize in Chemistry for the synthesis of cryptands Marko Leko (1853–1932), Serbian chemist known for work on the nature of ammonium chloride Luis Federico Leloir (1906–1987), Argentine biochemist and winner of the 1970 Nobel Prize in Chemistry Raymond Lemieux (1920–2000), Canadian organic chemist, Wolf Prize in Chemistry Gilbert Newton Lewis (1875–1946), American chemist and first Dean of the Berkeley College of Chemistry
== Comparative anatomy == Ligaments are similar to tendons and fasciae as they are all made of connective tissue. The differences among them are in the connections that they make: ligaments connect one bone to another bone, tendons connect muscle to bone, and fasciae connect muscles to other muscles. These are all found in the skeletal system of the human body. Ligaments cannot usually be regenerated naturally; however, there are periodontal ligament stem cells located near the periodontal ligament which are involved in the adult regeneration of periodontist ligament. The study of ligaments is known as desmology.
== Distribution == Psilocybe authority Gastón Guzmán, in his 1983 monograph on psilocybin mushrooms, considered Psilocybe semilanceata the world's most widespread psilocybin mushroom species, as it has been reported on 18 countries. In Europe, P. semilanceata has a widespread distribution, and is found in Austria, Belarus, Belgium, Bulgaria, the Channel Islands, Czech republic, Denmark, Estonia, the Faroe Islands, Finland, France, Georgia, Germany, Greece, Hungary, Iceland, India, Ireland, Italy, Latvia, Lithuania, the Netherlands, Norway, Poland, Romania, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and Ukraine. It is generally agreed that the species is native to Europe; Watling has demonstrated that there exists little difference between specimens collected from Spain and Scotland, at both the morphological and genetic level. The mushroom also has a widespread distribution in North America. In Canada it has been collected from British Columbia, New Brunswick, Newfoundland, Nova Scotia, Prince Edward Island, Ontario and Quebec. In the United States, it is most common in the Pacific Northwest, west of the Cascade Mountains, where it fruits abundantly in autumn and early winter; fruiting has also been reported to occur infrequently during spring months. Charles Horton Peck reported the mushroom to occur in New York in the early 20th century, and consequently, much literature published since then has reported the species to be present in the eastern United States.
Sources: en.wikipedia.org
=== 1960–1995 === Originally founded as Metropolitan Pathology Laboratory, Inc. in 1967 by Paul A. Brown, MD, the clinical laboratory underwent a variety of name changes. In 1969, the company's name changed to MetPath, Inc. with headquarters in Teaneck, New Jersey. By 1982, MetPath was acquired by what was then known as Corning Glass Works and was subsequently renamed Corning Clinical Laboratories.
==== COVID-19 ==== Epidemiological research has shown that the COVID-19 pandemic accelerated the opioid crisis. The overarching trend of opioid overdose data has shown a plateau in deaths around 2017–18, with a sudden and acute rise in 2019 primarily attributed to synthetic opioids like fentanyl. In 2020, there were 93,400 drug overdoses in the U.S. with >73% (approximately 69,000) due to opioid overdose. One JAMA review by Gomes et al. showed that estimated years of life loss (YLL) due to opioid toxicity in the U.S. increased by 276%. This increase was particularly felt by those ages 15 to 19, whose YLL increased nearly threefold. Younger male adults had the largest effect size. Other reviews of U.S. and Canadian opioid data coinciding with the onset of COVID-19 suggested significant increases in opioid-related emergency medicine utilization, increased positivity for opioids, and surprisingly no to decreased change in naloxone dispensation. Telehealth played a large role in OUD treatment access, and legislation on telehealth continues to evolve. A study of Medicare beneficiaries with new-onset OUD showed that those who received telehealth services had a 33% lower risk of death by overdose. Minority groups such as Black and Hispanic Americans have also been shown to benefit from the increased access due to telehealth programs introduced during the pandemic, despite increasing disparity gaps in other OUD-related outcomes. The DEA and HHS have extended telemedicine flexibility for prescribing controlled substances such as buprenorphine for OUD through 31 December 2024.\\
In his first two days as president, Biden signed 17 executive orders. By his third day, orders had included rejoining the Paris Climate Agreement, ending the state of national emergency at the border with Mexico, directing the government to rejoin the World Health Organization, face mask requirements on federal property, measures to combat hunger in the United States, and revoking permits for the construction of the Keystone XL pipeline. On March 11, Biden signed into law the American Rescue Plan Act of 2021, a $1.9 trillion economic stimulus and relief package that he had proposed to support the United States' recovery from the economic and health effects of the COVID-19 pandemic. The package included direct payments to most Americans, an extension of increased unemployment benefits, funds for vaccine distribution and school reopenings, and expansions of health insurance subsidies and the child tax credit. Biden's initial proposal included an increase of the federal minimum wage to $15 per hour, but after the Senate parliamentarian determined that including the increase in a budget reconciliation bill would violate Senate rules, Democrats removed it. Also in March, amid a rise in migrants entering the U.S. from Mexico, Biden said migrant adults were "being sent back", in reference to the continuation of the Trump administration's Title 42 policy for quick deportations.
On Christmas Eve, Humboldt and his party departed from Callao for Guayaquil, traveling slowly along the coast. During the voyage, Humboldt took regular oceanographic measurements of the cold current along the Peruvian coast. Although local fishermen had known of this current for centuries, Humboldt was the first to systematically study its properties. Over time, despite his protests, this current came to be widely known as the Humboldt Current, and it remains a principal geographical feature associated with his name. On February 15, 1803, Humboldt sailed from Guayaquil to Mexico. Even two hundred miles offshore, he heard the eruption of Cotopaxi. After thirty-three days at sea, the ship approached Acapulco. Humboldt discovered that standard charts had mislocated the port, a significant error given Acapulco’s importance as a hub for Spanish Pacific trade. On March 22, 1803, the ship anchored, and Humboldt began immediate astronomical observations to determine the port’s precise location. He confirmed that Acapulco was situated up to five miles west of its position on existing maps, prompting necessary revisions to the cartography of New Spain.
=== Differential diagnosis === The differential diagnosis for heel pain is extensive and includes pathological entities including: calcaneal stress fracture, septic arthritis, calcaneal bursitis, osteoarthritis, spinal stenosis involving the nerve roots of lumbar spinal nerve 5 (L5) or sacral spinal nerve 1 (S1), calcaneal fat pad syndrome, metastasized cancers from elsewhere in the body, hypothyroidism, gout, seronegative spondyloparthopathies such as reactive arthritis, ankylosing spondylitis, or rheumatoid arthritis (more likely if pain is present in both heels), plantar fascia rupture, and compression neuropathies such as tarsal tunnel syndrome or impingement of the medial calcaneal nerve. Diagnosis can usually be made based on medical history and physical examination. When a physician suspects a fracture, infection, or some other serious underlying condition, an X-ray is typical. X-rays are otherwise unnecessary.
Sources: en.wikipedia.org
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.
Laboratories use liquid chromatography-tandem mass spectrometry to detect GW501516 and its metabolites. Urine is commonly tested, and testing can occur in and out of competition.
No, cardarine is not a SARM. It is a PPARδ agonist, which acts on a different receptor. The two classes are often confused in online discussions.
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.