Cory Monteith has checked into rehab.

The 'Glee' actor - who plans Finn Hudson in the comedy-drama show and is dating his co-star Lea Michele - has ''voluntarily'' admitted himself into a facility for ''substance addiction''.

His representative told PEOPLE: ''[Cory] has voluntarily admitted himself to a treatment facility for substance addiction.

''He graciously asks for your respect and privacy as he takes the necessary steps towards recovery.''

Lea has vowed to stand by the 30-year-old hunk during his time in rehab and admitted she is ''grateful and proud'' of him for checking into the facility.

She added: ''I love and support Cory and will stand by him through this. I am grateful and proud he made this decision.''

Earlier today (01.04.13), she tweeted: ''Feeling so grateful today

Cory previously revealed he entered rehab when he was just 19 years old and encouraged others to seek help.

Speaking in an interview in 2011, he said: ''I don't want kids to think it's OK to drop out of school and get high, and they'll be famous actors, too.

''But for those people who might give up: Get real about what you want and go after it.''