Brianna McNeal, the Rio Olympic 100m hurdles champion, was provisionally suspended after being charged with tampering with part of a doping control process.
The Athletics Integrity Unit, which handles anti-doping cases in track and field, announced the ban on Thursday.
Provisional suspensions can be issued while awaiting a hearing on charges to determine an official punishment, if any.
McNeal, 29, led a U.S. medals sweep of the 100m hurdles in Rio.
She missed the 2017 World Championships while serving a one-year ban in a strange case of missing three drug tests in a 12-month span.