While Barton originally had been scheduled to serve as the celebrity host of the grand opening, her recent arrest for alleged drunken driving forced her to drop out, the Las Vegas Review-Journal reported Sunday.
Officials with CatHouse reportedly had temporarily targeted actress Rosario Dawson as a last-minute replacement for Saturday's event, but ultimately chose to forgo a celebrity presence.
"Because of Mischa Barton's current situation, CatHouse has decided it is best for all parties involved that Mischa does not appear at tonight's grand opening," the officials said in a statement. "Given the other celebrity attendance that is confirmed, CatHouse did not feel it necessary to replace Miss Barton as host."
Barton was arrested last Thursday in Hollywood after allegedly registering a 0.12 on a Breathalyzer test and being in possession of various drugs, the newspaper said.