Respected user , Hi
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I have evaluated your query thoroughly .
* Usually there is no such effect of Levosulpride molecule causing hard 
   stools  , still there are  always any remote  possibility of any unwanted 
   side  effect in  any single  individual  which  may  not  be noted till date .
*  My suggestions 
  -  Discontinue  the molecule  for  7  days  , watch  for  the  stool pattern
      if  it  returns  to  normal  without  doing  any other changes  in diet  or
      life  style  modifications  means  that  was  the  culprit .
      If  stool  still remains same then you need 
colonoscopy  work  up .
Hope to clarify  your query 
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Wishing fine recovery 
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