The NFL's rookie of the year will be suspended for the first four weeks of the season.
According to ESPN's Adam Schefter, Cushing is being suspended for violating the NFL's steroid policy.
Cushing appealed the league's decision at a hearing at the NFL scouting combine in February but was informed Friday his appeal had been rejected, according to sources.
He will be able to participate in training camp leading up to his suspension.
The Texans defense will suffer without Cushing, especially considering that its first game of the season is against the defending AFC South champion Indianapolis Colts. Cushing will also miss games against the Washington Redskins, Dallas Cowboys and Oakland Raiders.