Men with the most severe cases of PFB often cannot tolerate any shaving, but men with less severe PFB who can shave daily benefit form daily shaving. Strauss and Kligman [2] determined that daily shaving was actually the most effective shaving regimen to minimize lesions in most subjects, but could worsen the condition in those most prone to developing ingrown hair. Ideally, shaving on a daily basis is the most preferred, economical, and least invasive stratagems to manage the ingrown hair causing PFB.
Perricone [10] reported results of an investigator-blinded placebo-controlled study that demonstrated daily shaving resulted in a significant decrease in PFB lesions and the combination of daily shaving with glycolic acid treatment markedly reduced the number of PFB lesions compared to the shaving on a daily basis without glycolic acid. Daily shaving in both cases improved PFB in terms of lesion reduction. The mechanism of action of glycolic acid in enhancing the benefits of daily shaving was not clarified and speculations include an effect of glycolic acid on modification of skin surface or hair fiber structure to enhance shaving efficiency. Adhering to a daily shaving regimen is a difficult challenge for men with PFB and a critical observation from the studies on glycolic acid treatments was the self-reported claims by panelists that glycolic acid treatment actually facilitated compliance, with adherence to a daily shaving regimen. Indeed, the ability of glycolic acid to support maintenance of a daily regimen may have been the primary benefit of glycolic acid.
Preliminary pilot studies at the Gillette Research Institute on a panel of eleven men in a carefully monitored study which required all subjects to perform weekday shaving at the GRI demonstrated that seven weeks of alternate-day shaving produced a significant and stable 30% reduction in lesions from baseline, after both five and seven weeks of compliance with this regimen. Continued shaving on a daily basis for another five weeks resulted in a 60% reduction from baseline values. The results of a recent controlled – investigator blinded study commissioned by Gillette which was executed at the Wake Forest University Dept. of Dermatology have again demonstrated benefits of daily shaving versus alternate – day shaving. Eight weeks of daily shaving significantly reduced PFB lesions 38% from baseline in men who shaved on a daily basis compared to an 11% reduction of the lesions in men who shaved three times a week (manuscript submitted). The results of these studies reinforce the original observations of Kligman and Strauss, as well as the earlier reported research of dermatologists conducting closely monitored studies in military bases. It is important to emphasize that men with PFB are often reluctant to shave frequently because of pain and discomfort, and it is best to closely monitor the shaving frequency studies to be certain that participants are compliant.