What leads to or causes tardive dyskinesia?

"phenothiazines": Tardive means drug induced. Caused mainly by older major tranquilizers, also called typical anti-psychotics such as Haldol but also can happen with anti-nausea drugs like Reglan (metoclopramide) or Compazine that are structurally similar to Haldol type drugs. It is due to inhibition of Dopamine in the part of the brain called the basal ganglion.

Tardive dyskinesia: Tardive dyskinesia is most often a side effect of the use of antipsychotic medications when weaned, but can occur during treatment. If recognized early it may be temporary if the medication is discontinued. The symptoms can result from an excessive amount of the brain chemical Dopamine or excessively sensitive receptors for Dopamine present on certain brain cells involved in movement.