A serum containing Nyacinamide (Vitamin B3) and Papain (papaya enzyme) will be most effective at treating blackheads, Bratschi says. The Nyacinamide helps acne-affected skin and decreases oiliness, which is a blackheads causer. Papain is an exfoliant, which will help remove dead skin cells that clog pores. Try Glotherapeutics gloClear Healing Gel, $30.