Acne is caused by three things 1) overabundance of P.Acne on face 2) Abnormal shedding of skin 3) Overactive sebaceous gland activity on face. BP and Retin-A are two different medications that do DIFFERENT things. BP kills the P.Acnes on your skin and Retin-A corrects the abnormal shedding of the skin cells. Only Accutane can reduce the sebaceous gland activity. So in theory if you use BP in the day time to destroy the P.Acnes and Retin-A at night to correct the skin shedding, you should have clearer skin.

They do different things. BP kills bacteria and reduces inflammation. Retinoids change cell proliferation rates. Effects of BP can be seen more quickly. Retinoids take time to work, but are often more effective. Sometimes both are used in conjunction.