Which antipsychotics are least likely to cause weight gain?

Antipsychotics: Ziprazadone-Geodon and Lurasidone-Latuda, in my experience, are associated with weight loss. Quetiapine-Seroquel and Olanzapine-Zyprexa, cause the most weight gain, again in my experience. Those are all considered Second Generation Antipsychotics or Atypicals. All First Generation Antipsychotics cause weight gain. Great question. Wt gain is an important issue and preventing it can be a challenge.