There are four main reasons as to why patients believe that washing their acne will help.
First, they perceive that open comedones or blackheads are full of dirt. However, the black color of open comedones is not dirt. It was initially thought to be result of oxidation of fats; however, melanin staining has been incriminated by multiple studies.
Second, excessive sebum production occurs in most acne patients. This surface oil is perceived as dirty, and washing away these oils from the skin will stop pores blocking and decrease acne. However, these surface lipids have little to do with acne production, and while it is true that pores are functionally blocked, this is at a depth well beyond washing techniques, and attempts at scrubbing and obsessive washing will add nothing to management.
Third, patients believe that acne is an infection and that they are infectious to others. Although Propionobacterium acnes is important in the extension of the disease from simple comedones to full blown inflammatory lesions, it is a secondary phenomenon once the disease has been initiated. The relevant bacterium is an obligate anaerobe living in the oxygen free environment of the pilosebaceous apparatus and beyond any influence of surface washing.
Finally, because the use of topical and systemic antibiotics during acne treatment, the need for cleanliness is widely held — most patients will resort to cleansing products long before consulting a medical practitioner.
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