carcinogenicity comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-01-13. Where a claim depends on a specific study, the study is described rather than over-claimed.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
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.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
| Property | Value | Notes |
|---|---|---|
| IUPAC name | {4-[({4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl}methyl)sulfanyl]phenoxy}acetic acid | Systematic name for GW501516 |
| CAS Registry Number | 317318-70-0 | Unique identifier for the parent compound |
| Molecular formula | C21H18F3NO3S2 | Includes carbon, hydrogen, fluorine, nitrogen, oxygen, and sulfur |
| Molecular weight | 453.5 g/mol | Approximate value for the neutral form |
| Appearance | White to off-white powder | Typical description for purified laboratory material |
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.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
Published literature on cardarine includes in vitro assays, rodent experiments, and a small number of human studies. Reports describe effects on exercise capacity and lipid metabolism in animals, while human evidence is sparse. Many online descriptions present the compound as a proven endurance aid, a claim not supported by regulatory approval or large clinical trials. Analytical studies focus on identifying the parent compound and its metabolites in biological samples. Important uncertainties include species differences, dose-response relationships, and the relevance of rodent tumor findings to humans.
Adrenodoxin-NADP+ reductase (EC 1.18.1.6, adrenodoxin reductase, nicotinamide adenine dinucleotide phosphate-adrenodoxin reductase, ADR, NADPH:adrenal ferredoxin oxidoreductase) is an enzyme with systematic name adrendoxin:NADP+ oxidoreductase. This enzyme catalyses the following chemical reaction
In times of severe political confrontation and radical economic change, members of Mikołajczyk's agrarian movement (the Polish People's Party) attempted to preserve the existing aspects of mixed economy and protect property and other rights. However, after the 1947 elections, the Government of National Unity ceased to exist and the communists moved towards abolishing the post-war partially pluralistic "people's democracy" and replacing it with a state socialist system. The communist-dominated front Democratic Bloc of the 1947 elections, turned into the Front of National Unity in 1952, became officially the source of governmental authority. The Polish government-in-exile, lacking international recognition, remained in continuous existence until 1990.
== Composition == "Chains of Love" is an uptempo dance-oriented synth-pop track with Clarke's signature analogue sound and Bell's lyrics about breaking through any restrictions or stereotypes of what love should be. The lyrics allude subtly to Bell's desire for wider acceptance of gay couples, his pain evident from the opening lines "How can I explain when there are few words I can choose/How can I explain when words get broken".
=== Pseudobulbar affect === In 2010, the FDA approved the combination drug dextromethorphan/quinidine under the brand name Nuedexta for the treatment of pseudobulbar affect (uncontrollable laughing/crying). Dextromethorphan is the active therapeutic agent in the combination; quinidine merely serves to inhibit the enzymatic degradation of dextromethorphan and thereby increase its circulating concentrations via inhibition of CYP2D6.
Sources: en.wikipedia.org
== Ideology == SWAPO was founded with the aim of attaining the independence of Namibia and therefore is part of the African nationalist movement. Pre-independence it had a socialist, Marxist–Leninist ideology, which was not immediately abandoned when independence was achieved in 1990 and SWAPO became the ruling party. Officially, however, it adopted a social democratic ideology, until the electoral congress in 2017 approved the official change to socialism with a "Namibian character", although some Namibians have labelled the change as lacking a "grass-roots" nature. Various commentators have characterised the politics of SWAPO in different ways. Gerhard Tötemeyer, himself a party member, considered its post-independence politics neoliberal and social democratic. Henny Seibeb, an opposition politician from the Landless People's Movement, describes the current party ideology as liberal nationalism with traces of "dogmatism, authoritarianism, and statism".
Inhibition of transport by glutathione was enhanced by NADH. Gram-negative bacteria are protected against toxic electrophilic compounds by glutathione-gated potassium efflux systems (Kef) that modulate cytoplasmic pH. Roosild et al. (2010) have elucidated the mechanism of gating through structural and functional analysis of the E. coli KefC. The revealed mechanism can explain how subtle chemical differences in glutathione derivatives can produce opposite effects on channel function. Kef channels are regulated by potassium transport and NAD-binding (KTN) domains that sense both reduced glutathione, which inhibits Kef activity, and glutathione adducts that form during electrophile detoxification and activate Kef. Roosild et al. (2010) found that reduced glutathione stabilizes an inter-domain association between two KTN folds, whereas large adducts sterically disrupt this interaction. F441 is identified as the pivotal residue discriminating between reduced glutathione and its conjugates. They demonstrated a major structural change on the binding of an activating ligand to a KTN-domain protein. The MagA protein of Magnetospirillum sp. strain AMB-1 has been reported to be required for synthesis of bacterial magnetic particles. The magA gene is subject to transcriptional activation by an iron deficiency. However, a more recent report has shown that magA mutants of both Magnetospirillum magneticum AMB-1 and M. gryphiswaldense MSR-1 formed wild-type-like magnetosomes without a growth defect. Its transport function is not known.
== Toxicity == Information on the toxicity of 3-CMC is scarce, with only exploratory cytotoxicity studies conducted. Main concerns regarding toxicity of this compound origin in analogies to chloro-amphetamines (para-chloroamphetamine) which have confirmed neurotoxic effects. B-keto substitution in Cathinones completely alters their metabolism in comparison with amphetamines, rendering such analogies pointless. Recent study investigating toxicity of various chlorinated cathinones on SH-SY5Y human neuroblastoma cells showed LC50 (lower value indicating higher toxicity) of 2.1 mM for 4-MMC, 2.3 mM for 3-CMC and 1 mM for bupropion in study referred to as 3-Cl-TBC. To put that into perspective, similar studies show LC50 for 4-CA sitting around 0.5mM. Between November 2019 and June 2021, the EMCDDA reported ten deaths linked to 3-CMC exposure in Poland (7 cases) and Sweden (3 cases). Other substances were found in six cases, with alcohol being the only additional substance in two cases. Causes of death included multi-organ trauma caused by a traffic accident, toxic effects of 3-CMC, and intoxication with various substances. Details such as dosage and administration routes are lacking.
== O == octreotide - odorant receptor - olfaction - olfactory receptor neuron - oligopeptide - oncogene - oncogene protein - oncogene proteins V-abl - oncogenic retroviridae protein - open reading frame - opioid receptor - opsin - optical isomerism - organ (anatomy) - organelle - organic chemistry - organic compound - organic nomenclature - organic reaction - organism - osmosis - osteocalcin - outer hair cell - outline of biochemical techniques - ovalbumin - oxidation - oxidation number - oxidation state - oxidative decarboxylation - oxidative phosphorylation - oxygen - oxytocin - oxytocin receptor
It has been suggested that the same may have been true for clomipramine and other TCAs. Nonetheless, there is little doubt that many may, indeed, benefit from much higher doses. 250 mg/d, as mentioned elsewhere, is the typical maximum recommended dose but some people may need as much as 300 mg/d or more to benefit from all clomipramine has to offer beyond its potent SNRI capacity alone.
Sources: en.wikipedia.org
=== Excessive sleepiness === Selegiline has been evaluated for the treatment of narcolepsy in three small clinical studies. It was found to be effective in these studies. A dosage of 10 mg/day had no effect on symptoms, but 20 to 30 mg/day improved alertness, mood, and somewhat reduced cataplexy, clinical effects that have been described as comparable to the same dosages of amphetamine. Animal research indicates that the beneficial effects of high doses of selegiline in narcolepsy are likely due to conversion into its active metabolites, levoamphetamine and levomethamphetamine. Selegiline has also been evaluated for treatment of hypersomnia (excessive sleeping or sleepiness) in people with myotonic dystrophy, but its effectiveness was very uncertain.
=== Lebanon === In June 2025 Lebanese authorities uncovered a major criminal network that smuggled and sold counterfeit cancer drugs, including fake immunotherapy medication like IMFINZI (durvalumab), through Beirut's airport. These medicines contained no active ingredients and were substituted for real chemotherapy drugs, placing patients' lives at risk. The judicial inquiry, led by Judge Dora al-Khazen, has resulted in at least five arrests, including Mohamad Khalil (brother of former Finance Minister Ali Hassan Khalil), his ex-wife (a Beirut-area pharmacist), and a security officer who facilitated the smuggling. The scandal triggered emergency governmental action, widespread pharmacy raids, and significant public outrage, as lawmakers warned that up to one-third of medicines in Lebanon could be fake.
Human iron homeostasis is regulated at two different levels. Systemic iron levels are balanced by the controlled absorption of dietary iron by enterocytes, the cells that line the interior of the intestines, and the uncontrolled loss of iron from epithelial sloughing, sweat, injuries and blood loss. In addition, systemic iron is continuously recycled. Cellular iron levels are controlled differently by different cell types due to the expression of particular iron regulatory and transport proteins.
=== Ma–Me === Alan MacDiarmid (1927–2007), American-New Zealand chemist who discovered conductive polymers, 2000 Nobel Prize in Chemistry Carolina Henriette Mac Gillavry (1904–1993), Dutch chemist and crystallographer known for discoveries on the use of diffraction in crystallography Roderick MacKinnon (born 1956), American biophsicist known for work on ion channels; 2003 Nobel Prize in Chemistry Pierre Macquer (1718–1784), French chemist known for Dictionnaire de chymie Rudolph A. Marcus (1923–2026), Canadian chemist known for work on the theory of electron transfer reactions; 1992 Nobel Prize in Chemistry Jacob A. Marinsky (1918–2005), American chemist, co-discovered the element promethium Jean Charles Galissard de Marignac (1817–1894), Swiss chemist who discovered ytterbium and co-discovered gadolinium Vladimir Vasilevich Markovnikov (1838–1904), Russian chemist known for Markovnikov's rule describing addition reactions of hydrogen halides and alkenes Tobin J. Marks (born 1944), American inorganic chemist and materials scientist known for work in polymerization catalysts Alan G.
Sources: en.wikipedia.org
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.
It is prohibited by the World Anti-Doping Agency as a hormone and metabolic modulator. Athletes who test positive for GW501516 can face sanctions, including suspensions and loss of results.
Cardarine is a common or trade-style name, while GW501516 is the research code for the same chemical entity. Some sources also use Endurobol or GSK-516. The names refer to the same compound, not distinct drugs.
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.