British WBO middleweight world champion Billy Joe Saunders says he is a “clean fighter to the bone” following an adverse drugs test.
The 29-year-old returned an adverse analytical finding in a Voluntary Anti-Doping Association (Vada) test.
Promoter Frank Warren said the substance was in a “common decongestant nasal spray” and is permitted out of competition by UK Anti-Doping (Ukad).
Saunders is set to defend his title against Demetrius Andrade next month.
He said he was still “ready to go” for the bout against the American in Boston on 20 October.
“Thank you to my fans who stick by me – I’m a clean athlete and going be around a long time,” he added.
In a statement on Thursday, Warren said the British Boxing Board of Control (BBBofC) had confirmed Saunders had not breached its or Ukad’s anti-doping rules.
He added that Saunders, who is unbeaten in 26 bouts, was “therefore in good standing and is licensed to box and defend his world title on October 20th”.
ESPN has reported Saunders returned an adverse finding for stimulant oxilofrine in a test conducted by Vada on 30 August.
Under World Anti-Doping Agency (Wada) and Ukad rules, oxilofrine is only banned in competition, while it is prohibited at all times by Vada.
The BBBofC is affiliated to Ukad and Wada but not Vada, an organisation that boxers sign up to before fights to volunteer for random testing.
The Massachusetts State Athletic Commission, which adheres to the Wada prohibited list, will decide whether to license Saunders for the fight against American Andrade.
In April, Saunders called for WBC and WBA world middleweight champion Saul ‘Canelo’ Alvarez to be banned for life after failing two drugs tests.
Earlier this week Saunders was fined £100,000 by the BBBofC for misconduct after a video was posted on social media in which the fighter offers a woman £150 worth of drugs to perform a sex act. Saunders apologised for the video and described it as “banter” that “went wrong”.