Thanks for using this forum. As per your description this can be due to the sebaceous prominence which you are referring to can be a condition known as folliculitis
. The reasons for this can be diet,environmental or habitues changes which also can be leading to these appearing time and time again. You should consult with your physician who can examine your condition and accordingly prescribe you antibiotic course therapy. You should keep cleaning the area at intervals with cold
water and antibacterial soap,keep the area dry and wear loose clothings to avoid friction. Hope this helps. Regards.