Everything below concerns LC-MS/MS. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-08-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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 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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Common for reference-grade material. |
| Solubility | Low in water | Dissolves in DMSO and some organic solvents. |
| Typical storage | -20 °C, desiccated | Protect from light and moisture. |
| Analytical method | LC-MS/MS | Used for trace detection in biological matrices. |
| Purity assessment | HPLC with UV detection | Often combined with NMR and mass spectrometry. |
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
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.
Cardarine is the common name for GW501516, a synthetic compound studied as a peroxisome proliferator-activated receptor delta agonist. Researchers developed it to explore treatments for lipid disorders and metabolic conditions. It is not an approved medicine in any country. Early clinical work examined changes in HDL cholesterol and triglycerides, but development was discontinued after animal studies raised concerns about cancer. The compound remains available as a research chemical and appears in discussions of performance enhancement.
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.
=== Autoimmune processes === Research from 2007 suggested that in type 1 diabetics, the continuing autoimmune disease which initially destroyed the beta cells of the pancreas may also cause neuropathy, and nephropathy. In 2008 it was even suggested to treat retinopathy with drugs to suppress the abnormal immune response rather than by blood sugar control.
In 2001, a study of thagomizers by McWhinney et al. showed a high incidence of trauma-related damage. This too supports the theory that the principal function of the thagomizer was defense in combat. There is also evidence for a defense function in the form of an Allosaurus tail vertebra with a partially healed puncture wound that fits a Stegosaurus tail spike. This usage of the thagomizer would be similar to defensive behaviors in some extant lizards with tail spikes, such as the giant girdled lizard. The species of stegosaur known as Stegosaurus stenops had four dermal spikes, each about 60–90 cm (2–3 ft) long. Discoveries of articulated stegosaur armor show that, at least in some species, these spikes protruded horizontally from the tail, not vertically as is often depicted. Initially, Othniel Charles Marsh described S. armatus as having eight spikes in its tail, unlike S. stenops. However, recent research re-examined this and concluded this species also had four.
The requirement to remove surfactants, specifically SDS as used in Gel Elution Liquid-based Fractionation Entrapment Electrophoresis fractionation, prior to LC means that some proteoforms will be lost due to a lack of solubility after surfactant removal.
International law experts argued that the operation may have violated international law. On 3 January 2026, United Nations Spokesperson Stéphane Dujarric issued a statement that said the UN Secretary-General António Guterres was "deeply alarmed by the recent escalation in Venezuela" and that United States' military action "has potential worrying implications for the region". Lawyer Geoffrey Robertson stated that the strike on Venezuela was contrary to Article 2(4) of the UN Charter and qualifies as a crime of aggression under international law. Elvira Domínguez-Redondo, professor of international law at Kingston University, also stated the strike was an act of aggression and that it could only have been lawful if it had authorization by a United Nations Security Council resolution, or was justified as "self-defense", but she added that there was "no evidence whatsoever" to support either condition. Ben Saul, a UN special rapporteur and professor of international law, condemned "the US's illegal aggression against Venezuela and the illegal abduction of its leader and his wife" and called on Trump to be investigated and impeached. Professor of international law Michael N. Schmitt, law professor Ryan Goodman and Tess Bridgeman concluded that the operation against Venezuela "amounts to a severe breach of foundational principles of international law". Professor of law Ziyad Motala described the "intervention in Venezuela to abduct President Nicolás Maduro" as "international vandalism, plain and unadorned".
A notable application of these crystals is the development of quantum dots. Peidong Yang, another researcher from the University of California, Berkeley, is also notable for his contributions to the development of 1-dimensional nanostructures. The Yang group has active research projects in the areas of nanowire photonics, nanowire-based solar cells, nanowires for solar to fuel conversion, nanowire thermoelectrics, nanowire-cell interface, nanocrystal catalysis, nanotube nanofluidics, and plasmonics.
Sources: en.wikipedia.org
Obsessive–compulsive disorder (OCD), which happens to be its only US FDATooltip Food and Drug Administration-labeled indication. Other regulatory agencies (such as the TGA of Australia and the MHRA of the UK) have also approved clomipramine for this indication. A 2024 systematic review found that clomipramine is also effective in managing OCD in pediatric population. Major depressive disorder (MDD), a popular off-label use in the US. It is approved by the Australian TGA and the United Kingdom MHRA for this indication. In Japan it is also approved for depression. Some have suggested the possible superior efficacy of clomipramine compared to other antidepressants in the treatment of MDD, especially the more severe, although at the current time the evidence may be insufficient to more fully substantiate this claim. As-with other tricyclic antidepressants, the antidepressant response specifically may be augmented, including in treatment-resistant cases, with triiodothyronine, at a dosage of 50 mcg. In the case of clomipramine specifically, this may also be the case with OCD.
== History == Nalfurafine was derived from structural modification of the opioid antagonist naltrexone. It was first synthesized and characterized in 1998, and was approved for clinical use in Japan as an intravenous drug under the brand name Remitch in 2009. The developer of nalfurafine also sought approval in Europe under the brand name Winfuran, but the marketing authorisation application was declined by the European Medicines Agency. The drug was originally developed as an analgesic in surgery, but while effective in animal models of nociception, it was repurposed as an antipruritic at lower treatment doses due to an apparently unacceptable incidence of sedative effects in humans. As of 2015, nalfurafine is also in clinical trials for the treatment of cholestatic pruritus in Japan for patients with chronic liver disease, and for the treatment of uremic pruritus in the United States.
== Public health concerns == Epidemics of fatal pulmonary hypertension and heart valve damage associated with pharmaceutical anorectic agents have led to the withdrawal of products from the market. This was the case with aminorex in the 1960s, and again in the 1990s with fenfluramine (see: Fen-phen). Likewise, association of the related appetite suppressant phenylpropanolamine with hemorrhagic stroke led the Food and Drug Administration (FDA) to request its withdrawal from the market in the United States in 2000, and similar concerns regarding ephedrine resulted in an FDA ban on its inclusion in dietary supplements in 2004. A Federal judge later overturned this ban in 2005 during a challenge by supplement maker Nutraceuticals. It is also debatable as to whether the ephedrine ban had more to do with its use as a precursor in methamphetamine manufacture rather than health concerns with the ingredient as such.
== External links == Ernest Beutler (1928–2008) – Profile, including an oral history, from The American Society of Hematology. Scientific Publications – All publications of articles by Ernest Beutler listed in PubMed. Marshall A. Lichtman, "Ernest Beutler", Biographical Memoirs of the National Academy of Sciences (2012)
Although all anabolic steroids have androgenic effects, some of them paradoxically results in feminization, such as breast tissue in males, a condition called gynecomastia. These side effects are caused by the natural conversion of testosterone into estrogen and estradiol by the action of aromatase enzyme, encoded by the CYP19A1 gene. Prolonged use of androgenic-anabolic steroids by men results in temporary shut down of their natural testosterone production due to an inhibition of the hypothalamic–pituitary–gonadal axis. This manifests in testicular atrophy, inhibition of the production of sperm, sexual function and infertility. A short (1–2 months) use of androgenic-anabolic steroids by men followed by a course of testosterone-boosting therapy (e.g. clomifene and human chorionic gonadotropin) usually results in return to normal testosterone production.)
Sources: en.wikipedia.org
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.
Reference material is usually kept cold, dry, and protected from light. Frozen aliquots reduce repeated freeze-thaw cycles.
No approved pharmaceutical product exists, so manufacturing and quality controls are not standardized. Products may contain different compounds or impurities.
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.