Updated

A chimpanzee that mauled a Connecticut woman had the anti-anxiety drug Xanax in its system, according to toxicology tests, but investigators haven't determined whether the drug played a role in the attack, a prosecutor said Wednesday.

Authorities are still weighing whether to file criminal charges against the chimpanzee's owner, Sandra Herold, said Stamford State's Attorney David Cohen.

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The 200-pound chimp named Travis attacked Stamford resident Charla Nash on Feb. 16. She lost her hands, nose, lips and eyelids in the attack. Doctors at Ohio's Cleveland Clinic say she is blind and faces two years of surgical procedures.

Nash's family has sued Herold for $50 million. The suit alleges, among other things, that she had given Travis medication that further upset the animal.

"I think it provides tremendous support for the plaintiff's case," said Paul Slager, a catastrophic injury attorney in Stamford. "I think it's understood by everyone that Xanax is medication intended to be used by people, not animals."

He added: "I suspect that experts will agree it's difficult to predict how an animal like a chimpanzee would respond to taking a medication like Xanax."

Herold has made conflicting public statements about whether she gave Travis Xanax the day of the attack.

Herold's attorney, Robert Golger, declined to comment Wednesday, saying he hadn't seen the toxicology results, which were first reported by The Hour of Norwalk.

A telephone message left for an attorney for Nash's family wasn't immediately returned.

Herold's attorneys have said there was no way to predict Travis would attack Nash.

On the day of the attack, Herold called Nash to her home to help lure the animal back into her house.

Herold has speculated that the chimp was trying to protect her and attacked Nash because she had changed her hairstyle, was driving a different car and was holding a stuffed toy in front of her face to get Travis' attention.

The attack lasted about 12 minutes, and ended when police fatally shot Travis as he attempted to open a police cruiser's door.

Herold owned the 14-year-old chimp nearly all its life, dressed the animal and fed it human foods. When he was younger, Travis starred in TV commercials for Old Navy and Coca-Cola, made an appearance on the "Maury Povich Show" and took part in a television pilot.

Police Capt. Richard Conklin said a necropsy determined the chimpanzee died from multiple gun shot wounds. It also showed two substantial knife wounds to the back, confirming the owner's account that she stabbed her beloved pet with a butcher knife in an effort to rescue her friend, he said.

He said police will meet with experts in the coming weeks to try to determine if the level of Xanax found would affect the chimpanzee's behavior.

"It doesn't look like a large amount," of Xanax, Conklin said.

Humans who are aggressive or unstable can get worse under the influence of Xanax, said Dr. Emil Coccaro, chief of psychiatry at the University of Chicago Medical Center.

"They just have more frequent and severe outbursts," Coccaro said. He said he did not know how Xanax might affect a chimpanzee.