World marathon record-holder Ruth Chepng’etich has been provisionally suspended by the Athletics Integrity Unit (AIU) after testing positive for a banned substance, Hydrochlorothiazide (HCTZ), a diuretic commonly used to mask performance-enhancing drugs.

According to the AIU, a sample collected from Chepng’etich on March 14, 2025, revealed an alarming concentration of 3,800 ng/mL of HCTZ—significantly above the World Anti-Doping Agency’s (WADA) reporting threshold of 20 ng/mL.

AIU Head Brett Clothier confirmed that the Kenyan athlete was notified and interviewed on April 16 in Kenya. While an immediate suspension is not mandatory for diuretics under the World Anti-Doping Code, Chepng’etich voluntarily accepted a provisional suspension on April 19 as investigations progressed.

Months later, the AIU has now officially issued a Notice of Charge and imposed its own provisional suspension. Chepng’etich retains the right to a hearing before a Disciplinary Tribunal to contest the charges.

Hydrochlorothiazide is categorized under WADA’s S5 class of Diuretics and Masking Agents, which are banned at all times. Though used medically to treat conditions like high blood pressure, it is often misused in sports to conceal the presence of other prohibited substances.

If found guilty, Chepng’etich could face a standard suspension of two years, subject to mitigation or aggravation depending on the case specifics.

The AIU has stated that no further comments will be made until the disciplinary process concludes.