Russian Paralympian stripped of 2014 Sochi medals for doping breach
The IPC's Independent Anti-Doping Tribunal found that the cross country and biathlon athlete provided urine samples that had been tampered with.
As a result, Polukhin, now aged 42, has been stripped of a gold and two silver medals.
The IPC said investigations were carried out following World Anti-Doping Agency (WADA) evidence provided over state-sponsored doping in Russian sport between at least 2012 and 2015.
"During that time period, the Moscow and Sochi laboratories utilised a 'Disappearing Positive Methodology' to conceal presumptive adverse analytical findings and, at the Sochi 2014 Olympic and Paralympic Winter Games, swapped out 'dirty' urine samples for 'clean' urine obtained from athletes for that purpose," the IPC said in a statement.
Polukhin admitted using the heart medication trimetazidine (TMZ) out-of-competition in February 2014, which was permitted at that time, but denied knowledge of or participation in any sample swapping.
However, DNA analysis in 2018 confirmed that the urine swapped into the bottle was a match for the athlete.
"In the athlete's case, forensic analysis of the sample bottle showed scratches and marks and a urine residue tooth mark that could only have been caused by someone closing, then re-opening, then reclosing the sample bottle," the IPC said.
Jude Ellis, the IPC's Head of Anti-Doping, said: "Nikolay Polukhin's case met the evidential threshold to charge the athlete with an anti-doping rule violation.
"The resolution of this case draws a line under what has been a long running process into potential anti-doping rule violations by Russian athletes at the Sochi 2014 Paralympic Winter Games."