Drop column with constraints

gistfile1.txt

DECLARE @sql NVARCHAR(MAX)
WHILE 1=1
BEGIN
    SELECT TOP 1 @sql = N'alter table TABLE_NAME drop constraint ['+dc.NAME+N']'
    from sys.default_constraints dc
    JOIN sys.columns c
        ON c.default_object_id = dc.object_id
    WHERE 
        dc.parent_object_id = OBJECT_ID('TABLE_NAME')
    AND c.name = N'COLUMN_NAME'
    IF @@ROWCOUNT = 0 BREAK
    EXEC (@sql)
END

GO
alter table TABLE_NAME drop column COLUMN_NAME