marathon world record holder Ruth Chepngetich Ruth Chepngetich (full marathon 2024 Chicago 2:09:56 )has been banned for three years by the AIU (Athletics Integrity Unit) for violating anti-doping regulations. She admitted that hydrochlorothiazide (Hydrochlorothiazide, HCTZ) was detected in her system and that she had used the prohibited substance. The drug is a common diuretic, often used as a masking agent to hide the use of other stimulants.

Investigation timeline：

• March 14, 2025 

Ruth Chepngetich's test returned positive for HCTZ, with a concentration as high as 3,800 ng/mL—far above the 20 ng/mL reporting threshold set by WADA (World Anti-Doping Agency).

• 16 April 2025

During her first interview with AIU investigators she was unable to explain the test result. Investigators collected a complete list of all supplements and medications she had taken and seized physical samples of those products, and they also copied data from her phone for forensic analysis.

• 11 July 2025

AIU investigators showed Chepngetich suspicious material found on her phone that suggested possible deliberate use. Laboratory analysis confirmed that the supplement samples she submitted did not contain HCTZ.

• 31 July 2025

She changed her earlier account, claiming she had fallen ill two days before the test and had mistakenly taken her housemaid's medication, not knowing it contained hydrochlorothiazide. She provided a photo of the medication packaging, which was clearly labeled "Hydrochlorothiazide". However, the AIU did not accept this explanation, finding her conduct highly reckless and amounting to indirect intent.

• August 22, 2025

AIU issued a formal notice of charge, finding that she lacked a credible explanation and, citing "indirect intent", sought a four-year ban. Thereafter, Ruth admitted the violation and accepted the sanction within 20 days.

Under Article 10.8.1 of the anti-doping rules (early admission mitigation), the period of ineligibility was reduced to three years.