Nikita Lobintsev was already one of seven Russian swimmers banned from competing in the Rio Olympics by the International Swimming Federation (FINA) and USADA did not impose a new ban over the case.
On Thursday, the University of South California said it had suspended Russians Lobintsev and Vladimir Morozov from competing with its team.
USADA said the 27-year-old Lobintsev had been using meldonium for the past seven years. It was prescribed by Russia team doctors, who told him it would help strengthen his heart. Meldonium was added the World Anti-Doping Agency's banned list at the beginning of 2016.
Lobintsev, who told USADA he stopped using the drug 10 months ago, tested positive for meldonium on June 16 in an out-of-competition test.
"Based on the latest guidance offered by WADA on June 30, 2016, for cases involving meldonium, Lobintsev will not face a period of ineligibility or loss of results," the statement said.
The USC swim club said Thursday that Lobintsev and Morozov were no longer welcome to swim with the programme after they were named in an WADA investigation headed by Canadian law professor Richard McLaren.
Lobintsev, who won a silver medal at the 2008 Olympics and bronze at the 2012 Games, was banned from Rio after McLaren was able to show that Russian officials ordered a coverup of hundreds of doping tests.
"They would be stupid to knowingly engage in doping," Salo told the Los Angeles Times newspaper.
