Diarrhea or Constipation
can be due to side effects of Trazodone which is a Serotonin antagonist and reuptake inhibitors (SARIs) and used as antidepressant ang anxiolytic. You can switch to other Serotonin antagonist and reuptake inhibitors (SARIs) like Etoperidone , Lorpiprazole , Lubazodone , Mepiprazole , Nefazodone .or to Tricyclic antidepressants (TCAs) Amitriptyline
,Doxepin ,Imipramine ,Trimipramine ,Nortriptyline
,etc,. or better consult a Neuropsychiatrist.