Cushing's second career suspension begins immediately, although he was already ruled out of Thursday's game against the Cincinnati Bengals (0-1) after sustaining a concussion in last weekend's season-opening 29-7 loss to the Jacksonville Jaguars.
The 30-year-old Cushing will be eligible to return to the roster on Nov. 28, one day after Houston (0-1) faces the Baltimore Ravens.
Cushing is due a $6.756 million base salary this season. He will forfeit 10 game checks at a cost of $3.97 million, with a per week loss of $397,411.
Cushing's lawyer, Harvey Steinberg, said in a statement to ESPN that the linebacker "is aware of the negative impact he has had on his team and most important his fans. It is with the deepest remorse that he humbly apologizes to his fans, teammates and coaches."
Cushing will not appeal, according to Steinberg.
The 6-foot-3, 255-pound Cushing previously was suspended four games by the league in 2010 for testing positive for a fertility drug that was on the NFL's banned substances list. He said in a statement at the time that he tested positive for a non-steroidal banned substance, but his appeal proved unsuccessful.
Cushing, who had 65 tackles in 13 starts last season, underwent shoulder surgery during the offseason. He has collected 652 tackles, 13.0 sacks and eight interceptions in 100 career games since being selected by Houston with the 15th overall pick of the 2009 draft.