Bluish to black compressible lesions on lower lips are called venous lakes. They are benign but can be difficult to distinguish from melanomas. For this reason the first and the primary goal is to establish a diagnosis by seeing a competent and fully qualified dermatologist.
Small venous lakes will respond to laser treatment such as the Nd: YAG or pulsed dye laser.
The procedure is swift and for small lesions only one session is required. For larger lesions this can be undertaken under local anaesthetic and two or three sessions may be needed. There is a risk of small indent at the site of laser treatment especially with the Nd:YAG laser, but even this is barely noticeable.
Cold point cautery is an age old technique which is still very useful for removal of venous lakes.