How does Vistaril help with anxiety? Why else might Vistaril be prescribed? The side effects (of Vistaril) were too much for me. Now I take Atarax for anxiety and have noticed some of the same unpleasant side effects. Do either of these medications need to build up in the my body before becoming effective? Is it safe to stop these medications abruptly? I was told that Atarax and Vistaril are the same, except one is in capsule form and the other is a pill. Neither of these medications relieve my anxiety.