diff --git a/src/Oci8/Query/Grammars/OracleGrammar.php b/src/Oci8/Query/Grammars/OracleGrammar.php
index 40da6fa5..34a660c0 100644
--- a/src/Oci8/Query/Grammars/OracleGrammar.php
+++ b/src/Oci8/Query/Grammars/OracleGrammar.php
@@ -230,9 +230,9 @@ protected function wrapValue($value)
             return $value;
         }
 
-        $value = Str::upper($value);
+        $value = $this->isReserved($value) ? Str::lower($value) : Str::upper($value);
 
-        return '"' . str_replace('"', '""', $value) . '"';
+        return parent::wrapValue($value);
     }
 
     /**