Having a second look at your title, the following code might be what you are after:
For Each cell In Range(Cells(1, 1), Cells(1, Columns.Count).End(xlToLeft))
If cell.Value = "Dupes" Then
Range(Cells(2, cell.Column), Cells(Cells(Rows.Count, cell.Column).End(xlUp).Row, cell.Column)).RemoveDuplicates Columns:=1
Every column with a header named "Dupes" will get it's dupes removed. Change the word Dupes on the 3rd code line if you have/want another header name to trigger the removal of duplicates.