Delko rider banned for doping says he tested positive after eye surgery 

The UCI banned Atsushi Oka for four months after he was found to have a banned eye medication in his system

(Image credit: Corbis via Getty Images)

A Delko rider banned for doping has said he tested positive after having eye surgery. 

Atsushi Oka, who has ridden for the French ProTeam since 2020, has been banned by the UCI for four months after he tested positive for a banned substance in December last year. 

The 25-year-old, who hasn’t raced since September, was added to the UCI’s banned rider list after he was found to have the eye medication acetazolamide in his system during a test at the end of the season. 

In a statement released on social media Japanese pro Oka, the winner of one stage of the 2019 Tour of Japan, said the doping test took place four days after he had eye surgery in his home country.

Oka tested positive for the medication acetazolamide, sold under the trade name Diamox, which is an eye medication used in the treatment of glaucoma. 

The substance is banned by the World Anti-Doping Agency as a diuretic and masking agent.

Oka’s ban was backdated until January 2021, so will come to an end on May 25.  

Oka said: “It is important for me to point out that the control took place four days after an eye surgery that took place on December 9 in Japan, retaining acetazolamide absorption, a substance that comes from the Diamox [trade name for the drug] that was given to me during the procedure to prevent intraocular pressure spike, which may lead to partial or total visual field defect. 

“I have never used prohibited substances myself. The UCI accepted that it was unintentional and used for eye surgery treatment, I voluntarily accepted this suspension.

“I will come back on May 25 stronger and determined to return to the peloton."

Delko has not yet responded to Oka’s ban.

>>> Peter Sagan thanks team for ‘continued support’ amid contract uncertainty 

The squad are not the only ProTeam dealing with the fall-out of a doping ban, as Vini Zabù are currently serving a team-wide ban from racing after two of their riders tested positive within the space of 12 months. 

The Italian squad is now crowdfunding to pay for better anti-doping controls within the team, after they were forced to pull out of the Giro d’Italia as a result of the positives.  

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Alex Ballinger

Alex Ballinger is editor of BikeBiz magazine, the leading publication for the UK cycle industry, and is the former digital news editor for After gaining experience in local newsrooms, national newspapers and in digital journalism, Alex found his calling in cycling, first as a reporter, then as news editor responsible for Cycling Weekly's online news output, and now as the editor of BikeBiz. Since pro cycling first captured his heart during the 2010 Tour de France (specifically the Contador-Schleck battle) Alex covered three Tours de France, multiple editions of the Tour of Britain, and the World Championships, while both writing and video presenting for Cycling Weekly. He also specialises in fitness writing, often throwing himself into the deep end to help readers improve their own power numbers.  Away from the desk, Alex can be found racing time trials, riding BMX and mountain bikes, or exploring off-road on his gravel bike. He’s also an avid gamer, and can usually be found buried in an eclectic selection of books.