Six-time Olympic gold medallist Ryan Lochte has been suspended for 14 months for an anti-doping violation after he received an intravenous infusion, the US Anti-Doping Agency (USADA) announced on Monday.
While USADA said Lochte was not using a banned substance, athletes can typically only receive IVs as part of hospital treatment or through an exemption.
"I wasn't taking anything illegal. Everything was legal. You can get it at CVS, Walgreens, but there are rules, and you have to obey them," Lochte told a press conference in South Florida.
The 33-year-old American posted a picture of himself getting the IV on social media in May which caused USADA to open an investigation, one that Lochte "fully cooperated" with according to officials.
"Lochte received an intravenous infusion of permitted substances at an infusion clinic in a volume greater than 100 mL in a 12-hour period without a Therapeutic Use Exemption (TUE)," USADA said in a statement.
His ban was backdated to May 24, the date he received the treatment.
He will miss the US national championships which begin in California this week, next month's Pan Pacific Championships in Tokyo and the 2019 World Championships in South Korea.
In 2016, Lochte was banned from swimming for 10 months after he claimed that he and three other US swimmers were robbed after a night of revelry during the Rio Games.
Brazilian police later determined, in part based on surveillance video, that Lochte had largely fabricated the story.
He was charged with making a false crime report, but a Rio appeals court eventually threw that case out.