Hi,
This could be an eczema of the lips.The form of eczema that affects the
lips is known as cheilitis. This causes roughness to the
lips and can make them very sensitive, causing them to itch.
This eczema starts off with just a few rough patches on both of their lips, sometimes they are difficult to see, however they are painful to the touch.
These rough patches are not normally located inside the mouth, normally they are located where the lip joins onto the normal skin of the face.