I am sorry you are going through a rough patch, sincerely, time cures almost everything, keep going.
I suffer from agoraphobia ( and other conditions) too, and battle everyday for this horrible condition not to take over my life, and it's hard, I can relate to what you are feeling.
I have taken Zyprexa, brand name for Olanzapine, took it for 10 years for bipolar disorder, it helped.
You have become tolerant to the benzo Lorazepam (Ativan).
Now, this atypical antipsychotic, off label uses among some may help with anxiety, but try not to go down the road this drug class, it is a 2nd generation drug, meaning less potential side effects are expected to affect patients, everyone reacts differently to everything in life, in this case with medications.
From my experience of taking 2 antipsychotics for over 30 years, I am lucky, I have experienced mild side effects that did subside quite soon at the beginning of my treatment, they have helped me.
The FDA approved them for Schizophrenia and Bipolar Disorder, these conditions and others that I don't remember at this precise moment.
What I am trying to say is they are very good for the conditions mentioned, but to treat agoraphobia with these type of drugs is too much, before you take or decide to take Olanzapine, try different alternatives, antipsychotics are too much for going off label use in low doses treating different conditions unless you are treatment resistant to other meds, use them as a last resort.
All meds to me are serious and have risks and benefits, I believe you would benefit more changing from the Paxil (Paroxetine) to Prozac (Fluoxetine) another SSRIs.
How long have you been taking this AD of the SSRIs drug class and dose?
Talk to your Dr. about this possibility, it may help more and be more "gentle" than antipsychotics.
https://www.drugs.com/olanzapine.html
https://www.drugs.com/paxil.html
https://www.drugs.com/condition/agoraphobia.html
