The veteran was found to have tested for dexamethasone, phentermine, 19-noretiocholanolone, 19-norandrosterone, and an unnamed anabolic agent from an in-competition urine sample collected at the Tour of South Florida on February 5.

Dexamethasone is a glucocorticoid that is only prohibited in competition and is used to ease inflammation, with phentermine also banned only in competition.

Phentermine has effects similar to cocaine and is regarded as performance-enhancing.

19-noretiocholanolone, the metabolite of nandrolone, and its related substance bolandione, both performance-enhancing drugs, were also detected.

His sample was analysed by the United States Anti-Doping Agency through a specialised test called an isotope ratio mass spectrometry, which can differentiate between anabolic androgenic steroids naturally produced by the body and synthetic ones.

USADA and Ruiz-Gutierrez provided respective evidence on November 28 on the ban before the American Arbitration Association made a decision after the cyclist appealed the ban.

All of Ruiz-Gutierrez's results since February 5 have been disqualified and his period of ineligibility started on December 22 2022.