If you have been reading about GW501516 and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-09-21. Numbers and descriptions here follow the published literature rather than marketing material.
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.
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA as a PPARδ agonist. |
| Typical detection matrix | Urine | Most common sample for anti-doping analysis. |
| Common analytical method | LC-MS/MS | Liquid chromatography-tandem mass spectrometry. |
| Common synonyms | GW501516, GSK-516, endurobol | Names found in research and fitness contexts. |
| Typical detection window | Variable | Depends on dose, route, and individual metabolism. |
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
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 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.
Janet Cowell, Mayor Jonathan Melton, Council Member, At-large Stormie Forte, Council Member, At-large Mitchell Silver, Council Member (District A, north-central Raleigh) Megan Patton, Council Member (District B, northeast Raleigh) Corey Branch, Council Member (District C, southeast Raleigh) Jane Harrison, Council Member (District D, southwest Raleigh) Christina Jones, Council Member (District E, west and northwest Raleigh)
== Calcitonin gene-related peptide receptor == Agonists: Amylin CGRP Pramlintide Antagonists: Atogepant BI 44370 TA CGRP (8-37) MK-3207 Olcegepant Rimegepant SB-268262 Telcagepant Ubrogepant Antibodies: Eptinezumab Erenumab Fremanezumab Galcanezumab
=== Drug dependence === Gabapentin is moderately effective in reducing the symptoms of alcohol withdrawal and associated craving. The evidence in favor of gabapentin is weak in the treatment of alcoholism: it does not contribute to the achievement of abstinence, and the data on the relapse of heavy drinking and percent of days abstinent do not robustly favor gabapentin; it only decreases the percent days of heavy drinking. Gabapentin is ineffective in cocaine dependence and methamphetamine use, and it does not increase the rate of smoking cessation. While some studies indicate that gabapentin does not significantly reduce the symptoms of opiate withdrawal, there is increasing evidence that gabapentinoids are effective in controlling some of the symptoms during opiate detoxification. A clinical study in Iran, where heroin dependence is a significant social and public health problem, showed gabapentin produced positive results during an inpatient therapy program, particularly by reducing opioid-induced hyperalgesia and drug craving. There is insufficient evidence for its use in cannabis dependence.
Sources: en.wikipedia.org
== Histiocytic sarcoma complex == The histiocytic sarcoma (HS) complex encompasses a number of distinctive clinical entities which will be described below. Some definitions are in order, and reflect the preferred nomenclature of the writing group of the Histiocyte Society. Histiocytic neoplasia which originates at a single site is called histiocytic sarcoma. This form of histiocytic sarcoma, which is often encountered on the extremities, has the best prognosis if treated early by surgical excision or by amputation of a limb. When spread to distant sites beyond the local lymph node occurs, the disease is then termed disseminated histiocytic sarcoma; this is more likely to occur unnoticed when primary lesions occur in cryptic sites (e.g. spleen, lung, and bone marrow). This latter form of HS is most like malignant histiocytosis (MH). MH is an aggressive, histiocytic neoplasm which arises in multiple sites simultaneously. Most lesions previously defined as MH are probably more correctly termed disseminated HS. The occurrence of true MH is difficult to establish because the lesions often occur in cryptic sites, and the existence of histiocytic neoplasia is only recognized after clinical signs have appeared and disease progression is advanced. HS and MH are capable of widespread metastasis, hence in time the 2 syndromes merge clinically and it is not always possible to differentiate true multicentric origin (MH) from widespread metastasis of disseminated HS. Also, it is never possible to know exactly how long the disease process has been operative.
== Overdose == Mirtazapine is considered to be relatively safe in the event of an overdose, although it is considered slightly more toxic in overdose than most of the selective serotonin reuptake inhibitors (except citalopram). Unlike the tricyclic antidepressants, mirtazapine showed no significant cardiovascular adverse effects at 7 to 22 times the maximum recommended dose. Twelve deaths have been attributed to mirtazapine overdose. The fatal toxicity index (deaths per million prescriptions) for mirtazapine is 3.1 (95% CI: 0.1 to 17.2). This is similar to that observed with selective serotonin reuptake inhibitors.
Lungs and the entire respiratory system The entire digestive system including the liver Metabolism Skin, directly and indirectly through the intestine Hematopoietic organs It was generally described as a food capable of regenerating a weakened, emaciated, impoverished organism in an unusually short time, allowing the body to achieve better resistance. It was used by the Asian (Mongolian) equestrian peoples often as the only source of food for long periods and during high physical exertion, without the body developing symptoms of deficiency. Under Genghis-chan, the Mongols established a large empire. They moved on their horses across the steppes, deserts, and mountains and covered large distances, and for long periods they lived mainly on the milk of their mares, both fresh and fermented (kumyss). Around 1850, various Russian doctors observed the habits of the shepherds of the Baskirian steppe. They reported that the Basic and Tatars spent the winter in very unfavorable environmental conditions, with temperatures down to minus 60 °C, severe winter storms, and very little or no food. Weakened nomads regained their strength unusually quickly as soon as they fed on mare's milk. Russian doctors observed in the 19th century that tuberculosis was practically non-existent among the steppe nomads. Doctors attributed it to fermented mare milk as the staple food of the steppe people. When this became known in Russia, a migration of tuberculosis patients from Russia to the steppes began. The treatment was initially "wild", without medical supervision.
== Method == A model resonance ionization mass spectrometry (RIMS) set-up consists of a laser system (consisting of multiple lasers), sample from which the atoms are derived, and a suitable mass spectrometer which mass-selectively detects the photo ions created from resonance. In resonant ionization, atoms or molecules from ground state are excited to higher energy states by the resonant absorption of photons to produce ions. These ions are then monitored by appropriate detectors. In order to ensure a highly-efficient sensitivity and process saturation, the atomic or molecular beam must be formed from the ground state, the atoms should be efficiently excited and ionized, and each atom should be converted by the photon field of a short-timed pulsed laser to produce a positive ion and a valence electron. In a basic RIS process, a pulsed laser beam produces photons of the right energy in order to excite an atom initially in its ground state, a, to an excited level, b. During the laser pulse, the ion population of state b increases at the expense of that of state a. After a few minutes, the rate of stimulated emission from the excited state will equal rate of production so that the system is in equilibrium as long as the laser intensity is kept sufficiently high during a pulse. This high laser intensity translates into a photon fluence (photons per unit of beam area) large enough so that a necessary condition for the saturation of the RIS process has been met.
Sources: en.wikipedia.org
Yes, WADA prohibits cardarine as a PPARδ agonist. It appears on the prohibited list and can be detected in urine or blood. Athletes using it risk sanctions.
Detection usually uses liquid chromatography-tandem mass spectrometry after sample cleanup. Laboratories look for the parent compound or metabolites. The method requires validated reference standards and controls.
Legality varies by country. In many places it is an unapproved drug and cannot be legally sold for human consumption. Purchasing from online vendors carries legal and quality risks.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.