I doubt it was Xanax. Chimpanzees are truly savage, bestial creatures by their very nature, and supremely cunning and intelligent. They attack the limbs, faces, and genitals of their victims, showing they know exactly what they are doing, and are the only species of non-human animal that engages in purposeful torture, warfare, and ritual mutilation. A grown male chimp has the strength of at least ten humans and can take many bullets before it goes down.
Anybody who has a chimp as a "pet" is either completely insane or very ignorant of the true nature of this creature, and this beast's owner should be charged with attempted murder for what happened to that poor woman. I hate to curse G-d's creation, which technically is not sinful because it lacks free will, but this is one animal I would strongly consider giving the y-s to.
Edit: There is a lot of observational evidence that chimps absolutely have and exercise free will.