If you have access to reliably performed controlled studies done specifically on Unisom and/or Benadryl, I'd love to see them. I could only find poorly done anecdotal and/or observational studies, and only three of those.
All the rest were done on prescription meds, with the greatest and most potentially damaging medications found to be anticholinergic antidepressants, antipsychotic drugs, antiparkinson drugs, antiepileptic drugs, and bladder antimuscarinics ...
Given that Abilify is a fairly powerful anti-psychotic, there might be some concerns there, as well, even in modest doses for proscribed periods of time.