My mom is 88 years old and suffered a stroke 15 years ago. lately, she is hearing and seeing things. her doctor has put her on olanzapine. is it the right drug?

Disagree: The elderly can experience loss of hearing and vision, and not unique to have hallucination-like events involving misperceptions due to the losses. Certainly, medication reactions are also common. Anti-psychotics, like olanzapine, increase risk of death and stroke in elderly, and would not be my first choice unless really need to suppress behavior. Get this re-evaluated.

Zyprexa (olanzapine): Medications provide the symptomatic relief such as agitation or lack of sleep, but do not address the causes. Plus, side effects to medications are more common in elderly.

Possible delirium: With her previous hypertension, stroke, and age, your mother's hallucinations could be from delirium -- a confusional state caused by untreated medical issues like infections, metabolic problems (high blood sugar, electrolyte imbalance, etc) and many others. She needs focused workup of this new problem, which her doctor can begin. Olanzapine may cause problematic side effects on its own.