What Causes Disoriented Feeling And Depression While On Zyprexa?

I work with a lady that is in her early 30 s, is diagnosed with developmental disabilities, depression and anxiety. In the past two weeks, we have seen a significant increase in confusion, such as not knowing where the bathroom is, how to put her coat on, etc... This is not normal. She has has extreme crying episodes. She talks to people that are not present or have been deceased as if they are right beside her. Her support staff state that in the past, she has displayed similar episodes and usually is a sign of a UTI. She has been tested for UTI and had blood work completed. Nothing. She currently is taking Zyprexa 5 mg QPM. Is there somethng else that I need to have checked medically?