What is the major cause of blackheads? how can it be removed?

Blakcheads: They are caused by blocking of skin pores by gland secretions. It is an imbalance in the skin oil production. A dermatologist can help you treat them, there are a number of over the counter medications for acne and stronger prescription medications to treat the condition.

Acne: Blackheades or comedones is a form of acne. Unfortunately, no perfect treatment exists until your hormonal system settles down. There is a # of different treatments available but that would be better handled by a doc.