The backdated one-year suspension relates to a failed test given by the 22-year-old during last year's Copa America, where he tested positive for the banned diuretic hydrochlorothiazide.
Fred's punishment only relates to competitions under the jurisdiction of the South American Football Confederation (Conmebol), meaning he can continue to play for Shakhtar.
He is able to appeal the sanction but the ban will remain in place for the duration of any appeal process.
Fred has six caps for his country and the suspension is backdated to June 27 this year as he has not represented Brazil since their Copa America campaign.
"We got the decision for the one-year [ban], but it's retroactive so it starts from June 27, 2015, inclusive," Fred's legal representative Bichara Neto told UOL. "Therefore, he will serve the ban until June 26, 2016.
"We still have Conmebol's Appeal Chamber. We can appeal, so we'll analyse the decision and solve this."
The Confederation of Brazilian Football confirmed Fred's positive test in July and even if his ban is not reduced the player will be available to feature at the Olympic Games in Rio de Janeiro next year.