The short version of GW501516 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-06-08. Anything still debated is marked as such rather than presented as settled.
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.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | GW501516, GW-501516, GW 501516, endurobol | Names vary in research and anti-doping documents. |
| Chemical class | Synthetic PPARδ agonist | Small-molecule nuclear receptor ligand. |
| CAS Registry Number | 317318-70-0 | Identifier commonly associated with GW501516. |
| Appearance | White to off-white powder | Typical for purified research material. |
| Solubility | Low in water; soluble in DMSO and ethanol | Organic solvents are common for laboratory stock solutions. |
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.
Cardarine is explicitly prohibited by the World Anti-Doping Agency under the class of PPARδ agonists. Its presence in urine or blood samples can be detected using mass spectrometry-based methods, often liquid chromatography-tandem mass spectrometry. Athletes who test positive may face sanctions, including bans from competition. The compound is also regulated as a prescription-only or unapproved drug in many countries. Enforcement varies by jurisdiction, and some regions treat it as a controlled substance. Online sales may occur despite these restrictions, creating quality and legal risks.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
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.
Since 2005, law enforcement in the United States and elsewhere has seized several chemicals and combinations of chemicals in blotter paper which were sold as LSD mimics, including DOB, a mixture of DOC and DOI, 25I-NBOMe, and a mixture of DOC and DOB. Many mimics are toxic in comparatively small doses, or have extremely different safety profiles. Many street users of LSD are often under the impression that blotter paper, which is actively hallucinogenic, can only be LSD because that is the only chemical with low enough doses to fit on a small square of blotter paper. While it is true that LSD requires lower doses than most other hallucinogens, blotter paper is capable of absorbing a much larger amount of material. The DEA performed a chromatographic analysis of blotter paper containing 2C-C which showed that the paper contained a much greater concentration of the active chemical than typical LSD doses, although the exact quantity was not determined. Blotter LSD mimics can have relatively small dose squares; a sample of blotter paper containing DOC seized by Concord, California police had dose markings approximately 6 mm apart. Several deaths have been attributed to 25I-NBOMe.
=== Molecular Characterization === Dynamic light scattering (DLS) Matrix-assisted laser desorption/ionization (MALDI) spectrocosopy Nuclear magnetic resonance (NMR) spectroscopy Size exclusion chromatography (SEC)
=== Opioid use disorder === Buprenorphine is used to treat people with opioid use disorder. In the U.S., the combination formulation of buprenorphine/naloxone is generally prescribed to deter injection, since naloxone, an opioid antagonist, is believed to cause acute withdrawal if the formulation is crushed and injected. Taken orally, the naloxone is still capable of blocking the rewarding effects of Buprenorphine. Especially given its combination with certain medications that can reduce the metabolism of naloxone. Before starting buprenorphine, individuals with opioid dependence are generally advised to wait after their last dose of opioid, often 24–72 hours, because if taken too soon buprenorphine can displace other opioids bound to the receptors and precipitate an acute withdrawal. The dose of buprenorphine is then adjusted until symptoms improve, and individuals remain on a maintenance dose, often 8–16 mg. Because withdrawal is uncomfortable and a deterrent for many patients, users have called for different means of treatment initiation. The Bernese method, also known as microdose induction, was described in 2016, where very small doses of buprenorphine (0.2 to 0.5 mg) are given while patients are still using street opioids, with medicine levels slowly titrated upward without precipitating withdrawal. This method has been used by some providers as of the 2020s. Many of the publications on the Bernese method are case reports, case series, or clinical guidance rather than large randomized controlled trials (RCTs).
=== Pharmacokinetics === Metribolone has very low affinity for human serum sex hormone-binding globulin (SHBG), less than 5% of that of testosterone and less than 1% of that of dihydrotestosterone (DHT).
=== Books === Humphreys, Laud (1970), "Tearoom trade : impersonal sex in public places", Beiträge zur Sexualforschung, vol. 54, Duckworth, pp. 1–138, ISBN 978-0-7156-0551-6, OCLC 12118038, PMID 4466485 Humphreys, Laud (1972), Out of the closets; the sociology of homosexual liberation, A Spectrum book, S-288, Englewood Cliffs, N.J., Prentice-Hall, ISBN 978-0-13-645317-8, OCLC 357093
Sources: en.wikipedia.org
== See also == All pages with titles containing Link Linc (disambiguation) Lincs (disambiguation) Linker (disambiguation) Linq (disambiguation) Linx (disambiguation) Lynx (disambiguation) Microsoft Lync Linkt, road tolling brand in Australia
=== Lactose fermentation === In one study that sought to prove that some fermentation produced by L. lactis can hinder motility in pathogenic bacteria, the motilities of Pseudomonas, Vibrio, and Leptospira strains were severely disrupted by lactose utilization on the part of L. lactis. Using flagellar Salmonella as the experimental group, the research team found that a product of lactose fermentation is the cause of motility impairment in Salmonella. It is suggested that the L. lactis supernatant mainly affects Salmonella motility through disruption of flagellar rotation rather than through irreversible damage to morphology and physiology. Lactose fermentation by L. lactis produces acetate that reduces the intracellular pH of Salmonella, which in turn slows the rotation of their flagella. These results highlight the potential use of L. lactis for preventing infections by multiple bacterial species.
Now it is regarded as negative test; the acceptable level has been raised to ten parts per million for ephedrine and twenty-five parts per million for other substances. According to the IOC rules at the time, positive tests with levels lower than 10 ppm were cause of further investigation but not immediate ban. Neal Benowitz, a professor of medicine at UC San Francisco who is an expert on ephedrine and other stimulants, agreed that "These [levels] are what you'd see from someone taking cold or allergy medicines and are unlikely to have any effect on performance." Following Exum's revelations the IAAF acknowledged that at the 1988 Olympic Trials the USOC indeed followed the correct procedures in dealing with eight positive findings for ephedrine and ephedrine-related compounds in low concentration. Linford Christie of Great Britain was found to have metabolites of pseudoephedrine in his urine after a 200m heat at the same Olympics, but was later cleared of any wrongdoing. Of the top five competitors in the race, only former world record holder and eventual bronze medalist Calvin Smith of the US never failed a drug test during his career. Smith later said: "I should have been the gold medalist." The CBC radio documentary, Rewind, "Ben Johnson: A Hero Disgraced" broadcast on 19 September 2013, for the 25th anniversary of the race, stated 20 athletes tested positive for drugs but were cleared by the IOC at this 1988 Seoul Olympics.
== History == The traditional method for treating patients with dual diagnosis was a parallel treatment program. In this format, patients received mental health services from one clinician while addressing their substance use with a separate clinician. However, researchers found that parallel treatments were ineffective, suggesting a need to integrate the services addressing mental health with those addressing substance use. During the mid-1980s, a number of initiatives began to combine mental health and substance use disorder services in an attempt to meet this need. These programs worked to shift the method of treatment for substance use from a confrontational approach to a supportive one. They also introduced new methods to motivate clients and worked with them to develop long-term goals for their care. Although the studies conducted by these initiatives did not have control groups, their results were promising and became the basis for more rigorous efforts to study and develop models of integrated treatment. The COVID-19 pandemic has been associated with increased rates of substance use and psychological distress, potentially increasing co-occurring disorders in vulnerable populations.
Sources: en.wikipedia.org
== Education == Muhammad graduated from the School of Medicine, University of Ilorin in Nigeria. He was admitted to the school in 1987. He also studied at the University of Wales, United Kingdom where he obtained a master's degree in public health (1996) and the University of Nottingham where he obtained a master's degree in public administration.
=== Early pumps === The predecessor to the vacuum pump was the suction pump. Dual-action suction pumps were found in the city of Pompeii. The Arab engineer Al-Jazari later described dual-action suction pumps as part of water-raising machines in the 13th century. He also said that a suction pump was used in siphons to discharge Greek fire. The suction pump later appeared in medieval Europe from the 15th century.
The acidity of kombucha may be threatening to the demineralization of teeth, leading towards later tooth decay. Kombucha surpasses the critical pH of teeth, which is approximately 5.5, which disrupts the chemical stability of the enamel, leading to enamel erosion. Acids react with the bases within calcium hydroxyapatite, the primary component of tooth enamel, neutralizing them and increasing the dissolution of the enamel, causing degradation of the teeth. Drinking kombucha can be harmful for people with preexisting ailments. Due to its microbial sourcing and possible non-sterile packaging, kombucha is not recommended for people with poor immune function, women who are pregnant or nursing, or children under 4 years old: It may compromise immune responses or stomach acidity in these susceptible populations. There are certain drugs that one should not take with kombucha because of the small percentage of alcohol content. A 2019 review enumerated numerous potential health risks (including hyponatremia, lactic acidosis, toxic hepatitis, etc.), but said "kombucha is not considered harmful if about 4 oz [120 mL] per day is consumed by healthy individuals; potential risks are associated with a low pH brew leaching heavy metals from containers, excessive consumption of highly acidic kombucha, or consumption by individuals with pre-existing health conditions."
Sources: en.wikipedia.org
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.
No. Cardarine is not a steroid hormone; it targets the nuclear receptor PPARδ. Its classification in anti-doping rules differs from anabolic steroids, though it remains prohibited in sport.
Early rodent studies reported tumor formation at multiple sites, which raised safety concerns. Sponsors stopped clinical development, and no approved human product exists.
No. Cardarine is GW501516, a PPARδ agonist, while SARMs act on androgen receptors. The two classes are often grouped in informal discussions despite different mechanisms.