     and ds.vocabulary_id_1=cs.vocabulary_id
     and cs.vocabulary_id='RxNorm Extension'
     union all
-    select cs.concept_code, l.new_name
+    select distinct cs.concept_code, l.new_name
     from drug_strength_stage ds, concept_stage cs,
     lateral (
         select listagg(

--normalizing
merge into concept_stage cs
using (
    select cs.concept_code, l.new_name
    from drug_strength_stage ds, concept_stage cs,
    lateral (
        select listagg(

    and ds.vocabulary_id_1=cs.vocabulary_id
    and cs.vocabulary_id='RxNorm Extension'
	union all
    select distinct cs.concept_code, l.new_name
    from drug_strength_stage ds, concept_stage cs,
    lateral (
        select listagg(
