Is dystonia psychogenic?

Yes: Some patient exhibit psychogenic dystnia also.

Only sometimes: Most dystonia is involuntary and produced by neurological changes from medications such as antipsychotics, occasionally antidepressants, and some others (like reglan, (metoclopramide) etc). There can be psychogenic dystonia also, but it is only 1-5% of cases. A neurologist subspecializing in movement disorders can usually discern it from other types. http://mdc.mbi.ufl.edu/dystonia/psychogenic-dystonia.