Clostebol: accidental doping in sports

During the Indian Wells tournament in March, a top tennis player tested positive for a small amount of Clostebol, a banned steroid. The player said his fitness trainer bought a spray in Italy that had Clostebol and gave it to his physiotherapist to treat a cut. The physiotherapist then treated the player without gloves. The International Tennis Integrity Agency (ITIA) found that the banned substance got into player’s system by accident during a massage. They accepted his explanation and decided he didn’t break the rules on purpose, so he won’t be suspended. Clostebol can be detected in the body through various testing methods, primarily urine analysis. The detection threshold and sensitivity depend on the testing protocols used by anti-doping agencies. Here are some key points:

Detection thresholds of Clostebol

Urine tests: Clostebol and its metabolites can be detected in urine. The detection threshold for clostebol in urine is typically very low, often in the range of nanograms per milliliter (ng/mL). This means even small amounts can be detected.

Detection window: The detection window for clostebol depends on the dosage, frequency of use, and the individual’s metabolism. It can be detected for several days to weeks after the last dose. Detection of prohibited substances

Detection thresholds: Anti-doping agencies, like WADA, set specific detection thresholds for prohibited substances. These thresholds are designed to identify even small amounts of the substance that could indicate use. The detection devices are calibrated to these thresholds to ensure they can pick up even trace amounts.

Presence vs. quantity: If a prohibited substance is detected, it means the substance is present above the set detection threshold. This threshold is usually very low, so even minimal amounts can trigger a positive result. The focus is on the presence of the substance rather than the exact quantity.

Functional threshold of steroids

Minimum effective dose: Steroids like clostebol require a minimum effective dose to exert their anabolic effects. Below this dose, the steroid may not produce significant muscle growth or performance enhancement.

Dose-response relationship: The effects of steroids are dose-dependent. Higher doses generally lead to more pronounced effects, but also increase the risk of side effects.

Threshold for function: The specific minimum dose required for clostebol to be effective can vary based on individual factors such as metabolism, body weight, and overall health. However, there is a threshold below which the steroid would not exert its intended effects.

Key points

Detection: Devices are set to detect substances above a very low threshold, focusing on presence rather than quantity.

Function: Steroids need to be present in sufficient quantities to exert their effects; below this threshold, they may not be effective.

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Clostebol, also known as 4-chlorotestosterone, is a synthetic anabolic-androgenic steroid (AAS) derived from testosterone. It has a chlorine atom at the 4th position, which prevents its conversion to dihydrotestosterone (DHT) and estrogen.

Uses and applications:

Medical uses: Clostebol acetate ointment is used in ophthalmology and dermatology for its anti-inflammatory and healing properties.

Performance enhancement: It is sometimes used as performance-enhancing drug, although it is banned by the World Anti-Doping Agency (WADA).

Side effects:

Potential side effects include those common to anabolic steroids, such as liver toxicity, hormonal imbalances, and cardiovascular issues.

Regulation:

Clostebol is classified as a prohibited substance in sports and has led to the suspension of several athletes.

References Jannik Sinner tested positive for the steroid clostebol | AP News. What is clostebol, a substance that banned many athletes? (antidopingdatabase.com). Clostebol Explained – IronMag Bodybuilding & Fitness Blog (ironmagazine.com). Detection of clostebol in sports: accidental doping? | World Anti Doping Agency (wada-ama.org). Bond, P., Smit, D.L. and de Ronde, W., 2022. Anabolic–androgenic steroids: How do they work and what are the risks?. Frontiers in Endocrinology, 13, p.1059473.