How can antipsychotics work for anxiety?

Any: All antipsychotics decrease Dopamine and effect other neurotransmitters in various ways. There are many other treatments for anxiety with fewer side effects such as antidepressants, buspar, (buspirone) hydroxyzine, and benzodiazepines. As with any medication, it is always a matter of choosing the one with the most benefit and the least amount of side effects.

Anxiety: Antipsychotics, especially sedating ones, are occasionally used for agitation, especially in bipolar or psychotic cases, not for anxiety per se.