Expired medication

Has anyone taken any experired medication. Im taking prozac which is not expired. But the ativan I was taking was since last year. The doctor told me it has the same effect still. But the pharmacist said after a month expired the chemical can change.

I was given that too Clay. Is it to help you sleep too? How expired?

2 Dr’s told me they don’t expire.  I’m using Xanax from 3 years ago and it seems to work the same.

One year and a half.