What do you get when you add VH1, eight washed-up has-beens, and a moratorium on vodka?

Chick fight!

We’re barely two weeks into filming on Celebrity Rehab with Dr. Drew. 4 and already two of the most-chatted members of the season’s C-Level cast are at war.

RadarOnline.com reports that celebrity semen receptacle Rachel Uchitel and batty former supermodel Janice Dickinson hate each other and spend hours on end barking insults behind the walls of the Pasadena Recovery Center. The plastic surgery-obsessed pair are seeking help for addiction to alcohol. Sadly for those within earshot of their violent quarrels, sobriety hasn’t been very useful in getting the gals to build bridges.

Go figure.

“Rachel hates Janice and Janice hates Rachel. Janice thinks Rachel is an opportunist, and Rachel thinks Janice is a has-been,” a source tells Radar. “They haven’t gotten along since the beginning. They get into frequent loud arguments and it’s getting disruptive for the others. Janice frequently rolls her eyes when Rachel is talking in the group therapy sessions.”

Meanwhile, Uchitel, an alleged former mistress of David Boreanaz and Tiger Woods, reportedly fled rehab earlier this week after an intense session with Dr. Drew.

Producers talked Uchitel into returning.