GW501516 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.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
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 |
|---|---|---|
| Appearance | White to off-white solid | Typical form of reference material |
| Solubility | Low in water; soluble in DMSO | Used to prepare stock solutions |
| Typical storage | -20 °C, desiccated, protected from light | Common laboratory practice |
| Analytical method | LC-MS/MS | Detects parent compound and metabolites |
| Common test matrix | Urine or blood | Used in anti-doping analysis |
Regulatory bodies treat GW501516 as a prohibited substance in competitive sport. The World Anti-Doping Agency added it to the prohibited list, and it falls under classes covering metabolic modulators and hormone-related agents. It is not approved by drug regulators for human use, and it is not a lawful dietary supplement. Products sold under the cardarine name may contain unlisted ingredients or different compounds. Because no approved product exists, quality and identity are not guaranteed by pharmaceutical manufacturing standards.
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.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
According to a recent patent application, yields of up to 95% are obtained with the same starting materials in toluene in the presence of potassium methoxide. It is subject to keto-enol tautomerism and exists predominantly enol when dissolved. Upon UV radiation, it may convert to keto form, while converting back to enol form after placing in dark.
Pauling also criticised the Mayo Clinic studies because the controls were taking vitamin C during the trial, and because the duration of the treatment with vitamin C was short; Pauling advocated continued high-dose vitamin C for the rest of the cancer patient's life whereas the Mayo Clinic patients in the second trial were treated with vitamin C for a median of 2.5 months. Ultimately the negative findings of the Mayo Clinic studies ended general interest in vitamin C as a treatment for cancer. Despite this, Pauling continued to promote vitamin C for treating cancer and the common cold, working with The Institutes for the Achievement of Human Potential to use vitamin C in the treatment of brain-injured children. He later collaborated with the Canadian physician Abram Hoffer on a micronutrient regime, including high-dose vitamin C, as adjunctive cancer therapy. A 2009 review also noted differences between the studies, such as the Mayo Clinic not using intravenous Vitamin C, and suggested further studies into the role of vitamin C when given intravenously. Results from most clinical trials suggest that modest vitamin C supplementation alone or with other nutrients offers no benefit in the prevention of cancer.
After nearly a decade's absence, Dunkin' Donuts returned to the state of Minnesota in 2014; a new shop opened inside the Kahler Grand Hotel in Rochester. In the United States, Dunkin' is sometimes paired with Baskin-Robbins ice cream in a single multibranded store. While such locations usually maintain separate counters for each chain (much like co-branded Wendy's–Tim Hortons locations in Canada), depending on business that day, both chains' products can be bought at a single counter (typically Dunkin' Donuts'). The practice of single-counter service is similar to that of multibranded Yum! Brands stores such as KFC–Taco Bell, which share a single kitchen and cashier line. As of February 9, 2017, all Dunkin' locations are franchisee owned and operated. In addition to its stand-alone shops, Dunkin' shops can be found within many gas stations, supermarkets, mall and airport food courts, and Walmart stores. In July 2013, Dunkin' Donuts opened its 500th restaurant in New York City. This location is combined with a Baskin-Robbins. On July 30, 2020, Dunkin' Brands announced it would permanently close 800 stores in the US by the end of the year because of a 20 percent drop in sales in the second quarter during the COVID-19 pandemic, 450 of which are part of the previously announced closing of locations within Speedway gas stations. As of 2019, 40 Dunkin' Donuts shops in the United States were certified fully kosher, in addition to one that sells both kosher-certified and non-kosher products.
=== Food product design === Food designers use water activity to formulate shelf-stable food. If a product is kept below a certain water activity, then mold growth is inhibited. This results in a longer shelf life. Water activity values can also help limit moisture migration within a food product made with different ingredients. If raisins of a higher water activity are packaged with bran flakes of a lower water activity, the water from the raisins migrates to the bran flakes over time, making the raisins hard and the bran flakes soggy. Food formulators use water activity to predict how much moisture migration affects their product.
Sources: en.wikipedia.org
β1Rs preferentially bind epinephrine, along with norepinephrine to a lesser extent and mediates some of their cellular effects in cardiac myocytes such as increased positive inotropy and lusitropy. β-blockers exert their cardioprotective effects through decreasing oxygen demand in cardiac myocytes; this is accomplished via decreasing the force of contraction during systole (negative inotropy) and decreasing the rate of relaxation during diastole (negative lusitropy), thus reducing myocardial energy demand which is useful in treating cardiovascular disorders accompanied by inadequate myocardial oxygen supply. Alpha blockers, which counter the effects of noradrenaline on alpha-adrenergic receptors, are occasionally used to treat hypertension and psychiatric conditions. Alpha-2 agonists often have a sedating and antihypertensive effect and are commonly used as anesthesia enhancers in surgery, as well as in treatment of drug or alcohol dependence. For reasons that are still unclear, some Alpha-2 agonists, such as guanfacine, have also been shown to be effective in the treatment of anxiety disorders and ADHD. Many important psychiatric drugs exert strong effects on noradrenaline systems in the brain, resulting in effects that may be helpful or harmful.
In January 2026, the American Civil Liberties Union, Center for Constitutional Rights, and Jonathan Hafetz filed a federal lawsuit against the United States government on behalf of the families of two people from Las Cuevas, Trinidad and Tobago who were killed in a strike on 14 October 2025. The lawsuit alleged that the strikes were "premeditated and intentional killings" that "lack any plausible legal justification" and were "simply murder, ordered at the highest levels of government and obeyed by military officers in the chain of command."
== Medicines == Treatments based on monoclonal antibodies have been produced related to CGRP or CGRP receptors. They have been shown to be effective in patients who experience migraine headaches, both with and without aura, and both episodic and chronic cluster headache. These are the first class of preventive medications originally designed and approved for people with migraine. Due to the nature of the monoclonal antibodies, they must be administered parenterally, preferably by injection. The first CGRP related medication approved by the FDA is called erenumab (trade name Aimovig), produced by pharmaceutical company Amgen and Novartis. It interacts with the CGRP receptor. It is injected once monthly with a dose of 70 or 140 mg. Few adverse effects were reported (most related to injection site reactions) and patients had a significant reduction in migraines. The second approved by the FDA is fremanezumab (trade name Ajovy), produced by the Teva Pharmaceuticals company. It interacts with the CGRP protein, whose expression is related to migraine attacks. It may be administered monthly or every three months, giving options for users. Trials have shown a reduction of greater than 50% of migraine days for those who responded. There were few significant side effects during trials, most related to injection site reactions. The third CGRP medication approved by the FDA is galcanezumab (trade name Emgality), produced by the Eli Lilly and Company. It interacts with the CGRP protein, whose expression is related to migraine attacks.
=== Depersonalization === Naltrexone is sometimes used in the treatment of dissociative symptoms, such as the depersonalization and derealization of depersonalization-derealization disorder. Some studies suggest it might help, but conclusions are limited by a small evidence base. Blockade of the KOR by naltrexone and naloxone is thought to be responsible for their effectiveness in ameliorating depersonalization and derealization. Since these drugs are less efficacious in blocking the KOR relative to the MOR, higher doses than used in opioid dependence therapy seem to be necessary.
==== Binge eating disorder ==== Binge eating disorder (BED) is characterized by recurrent and persistent episodes of compulsive binge eating. These episodes are often accompanied by marked distress and a feeling of loss of control over eating. The pathophysiology of BED is not fully understood, but it is believed to involve dysfunctional dopaminergic reward circuitry along the cortico-striatal-thalamic-cortical loop. As of July 2024, lisdexamfetamine is the only USFDA- and TGA-approved pharmacotherapy for BED. Evidence suggests that lisdexamfetamine's treatment efficacy in BED is underpinned at least in part by a psychopathological overlap between BED and ADHD, with the latter conceptualized as a cognitive control disorder that also benefits from treatment with lisdexamfetamine. Lisdexamfetamine's therapeutic effects for BED primarily involve direct action in the central nervous system after conversion to its pharmacologically active metabolite, dextroamphetamine. Dextroamphetamine increases dopaminergic and noradrenergic neurotransmission in prefrontal cortex, a region of the brain that regulates cognitive control of behavior. Similar to its therapeutic effect in ADHD, dextroamphetamine enhances cognitive control and may reduce impulsivity in patients with BED by enhancing the cognitive processes responsible for overriding prepotent feeding responses that precede binge eating episodes.
Sources: en.wikipedia.org
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.
PPARδ is a nuclear receptor that regulates genes linked to fatty acid oxidation and energy metabolism. Activation can alter lipid handling and energy use in experimental models. The full range of effects in humans is still under study.
The solid compound is generally stable when kept cold, dry, and protected from light. Solutions may degrade faster, so laboratory protocols often specify fresh preparation or cold storage. Stability can depend on solvent, concentration, and container.
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.