has completed treatment for substance-abuse issues, his rep has confirmed to PEOPLE.
"Gerard has completed a successful course of treatment and has returned home in good health," says the spokesperson. "We will not be making any further comment at this time."
Butler, 42, checked himself into the Betty Ford clinic three weeks ago because he realized he was becoming reliant on prescription drugs after being badly injured in a surfing accident
in December, TMZ reports
He allegedly decided to enter rehab before developing a full-blown addiction to the drugs.
Butler's issues reportedly date back to 2006, when he began struggling with pain management while shooting the physically demanding 300
. The surfing accident occurred on the set of his latest film, Of Men and Mavericks
According to the TMZ report, the Scottish actor had also "developed issues" relating to cocaine, but his primary concern was the prescription drugs.
Butler has long been open about his past problems with alcohol abuse. "I used to drink until I couldn't remember anything," he told The Red Bulletin
(via Radar online). "I was just mad for it and on a death wish. It was madness."
With reporting by JULIE JORDAN