In a notice on Thursday, October 23, the AIU revealed the 31-year-old marathoner admitted to using the banned diuretic Hydrochlorothiazide (HCTZ).
The positive test came from a sample collected on March 14, whereby AIU investigations revealed concentrations of the banned substance in her urine sample.
“Women’s marathon world record holder, Ruth Chepng’etich, has been banned for three years by the Athletics Integrity Unit (AIU), after admitting to Anti-Doping Rule Violations (ADRVs) regarding the presence and use of Hydrochlorothiazide (HCTZ),” a statement from the AIU read.
According to AIU, Hydrochlorothiazide (HCTZ) is typically used by athletes in large doses to mask the presence of other prohibited substances. While it is not entirely banned, the World Anti-Doping Agency (WADA) has a stipulated limit which can be used by professional athletes.
Chepng’etich was initially interviewed in April 2025, and according to the AIU, she could not explain the positive result of her initial tests.
Investigators collected evidence, including supplements, medications and her mobile phone for further analysis. All samples tested negative for the substances.
In a subsequent interview in July, evidence from her phone raised further suspicions that the positive test may have been intentional, but the marathon star maintained her innocence and denied any involvement in any doping.
What appears to have hampered Chepng’etich’s chances of avoiding a ban was the fact that she altered her story, stating that she had taken her domestic manager’s medication two days before the positive test without checking if it contained banned substances.
The AIU deemed the explanation not credible under anti-doping rules, as the explanation was deemed reckless and counted as indirect intent to dope, warranting a four-year ban.
However, because the athlete admitted fault and conceded her sanctions early, the ban was revised to three years.
Chepng’etich, who won the Chicago Marathon for the third consecutive time, broke the previous world record of 2:11:53, which had been set by Ethiopian Tigst Assefa at the 2023 Berlin Marathon.
(Kenyan co)
