The player – who was not named – was initially suspended for 30 days on Thursday, however that decision has been swiftly overturned by FIFA.
It was announced that the individual's 'A' sample had revealed the presence of substances prohibited by the World Anti-Doping Agency (WADA) in a test conducted following Bulgaria's FIFA World Cup qualifier with Malta on September 10.
However, later on Thursday football's governing body released a new statement overturning the decision.
It read: "The chairman of the FIFA Disciplinary Committee has revoked his decision to suspend a Bulgarian international footballer for a period of 30 days.
"The decision was taken following clarification by medical bodies, on the basis of which it appears that there is no circumstantial evidence that anti-doping rules have been violated."
Bulgaria sit second in their World Cup Qualifying group with two games remaining.
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