diff --git a/models/omop/drug_era.sql b/models/omop/drug_era.sql
index d60f3df..ac8270a 100644
--- a/models/omop/drug_era.sql
+++ b/models/omop/drug_era.sql
@@ -12,10 +12,10 @@ WITH ctePreDrugTarget AS (
         , COALESCE(
             NULLIF(drug_exposure_end_date, NULL)
             , NULLIF(
-                drug_exposure_start_date + days_supply * INTERVAL '1 day'
+                {{ dateadd("day", "days_supply", "drug_exposure_start_date") }}
                 , drug_exposure_start_date
             )
-            , drug_exposure_start_date + INTERVAL '1 day'
+            , {{ dateadd("day", 1, "drug_exposure_start_date") }}
         ) AS drug_exposure_end_date
     FROM {{ ref ('drug_exposure') }} AS d
     INNER JOIN {{ ref ('stg_vocabulary__concept_ancestor') }} AS ca