Lindsay Lohan (file photo)

Lindsay Lohan's out of rehab...and back on the party circuit. The 21-year-old actress completed a 45-day residential substance abuse treatment program July 13, and the following night was seen at a Las Vegas nightclub.

In a statement to Access Hollywood, publicist Leslie Sloan Zelnick said Lohan is now in an outpatient program comprising daily attendance at Alcoholics Anonymous meetings, outpatient therapy, and daily testing.

Zelnick said Lohan has also chosen to wear an alcohol-monitoring bracelet. Known as a "scam bracelet," it downloads information every 30 minutes to a computer, and is reportedly 100 percent accurate.

Lohan was seen Saturday night at Pure nightclub in Las Vegas, reportedly to celebrate a friend's birthday. She was said to be drinking Red Bull energy drink and water.

Lindsay Lohan was arrested in May on suspicion of driving under the influence of alcohol. She checked into the Promises Malibu Alcohol and Drug Rehab Treatment Facility on May 28.