Mejia is eligible to apply for reinstatement in one year, but he must sit out a minimum of two seasons even if his reinstatement is granted by MLB.
Mejia is the first player in Major League history to be permanently suspended under the new Joint Drug Agreement, established in December 2011.
Under the policy, a first-time offender is suspended 80 games. A second-time offender is suspended 162 games. Finally, a player suspended a third time will be placed on MLB's Restricted List.
Mejia's first suspension came on April 11, 2015, when he was barred 80 games for the use of stanozolol. On July 28, it was announced that he failed a test for stanozolol and Boldenone and received a 162-game suspension.
The 26-year-old Mejia was signed by the Mets as an amateur free agent in 2007 and was rushed to the big leagues in 2010.
He came into his own in 2014, going 6-6 with a 3.65 ERA with a 98 to 41 strikeout-to-walk ratio (3.73 FIP) in 93 2/3 innings pitched. Mejia saved 28 games in 31 opportunities.
Over his career, Mejia went 9-14 with a 3.68 ERA and a 2.13 strikeout-to-walk ratio in 183 1/3 innings pitched over five years with the Mets.