Dizziness and headache are side effects of Olanzapine. I would avoid it unless it is absolutely necessary. If you look at other people with sensitivities like yours, antidepressants or antipsychotics are often involved. Any drug that affects the neurotransmitters in the brain is bad for the brain.

You may have to taper the dose down if the withdrawal effects are bad.

Take a look at this book. It talks about anxiety and depression. The chemicals from medications accumulate in your body, so a detox plan would be good and can be used in conjunction with medications. It Takes Guts To Be Happy: A 21-Day Cleansing Plan to Heal Your Belly & Recharge Your Life