Bam Margera left detox early and is telling friends he's going to spend the weekend in Las Vegas ... sources familiar with the situation tell TMZ.
The former "Jackass" star had been detoxing in San Diego at a place Lamar Odom helped him get in, but we're told Bam didn't want to complete the program ... and on Monday he bounced.
Our sources say Lamar was desperately trying to get Bam to return to the detox center and finish up at Odom Wellness Treatment Centers, but Bam instead agreed to stay at Lamar's home in Calabasas this week, with Lamar continuing to encourage Bam to finish treatment.