So very sorry. My nephew had this and his mother was very worried about the Accutane, but it was a godsend and she was sorry that she didn't try it earlier. Try not to stress too much about it. Go ahead and try it.
My sons had moderate acne. Their dermatologist had an esthetician on staff. I took them on a regular basis to her for microdermabrasion for both face and back. It was SO worth the money, E.. A good esthetician with a good machine can make a huge difference in your son's skin. There is a sticky substance on the skin that holds in the impurities and oils. This procedure removes the sticky substance and pulls out the impurities. It makes it easier for the medicine that they put on the face to actually reach down into the skin as well.
My son's esthetician also used a curette to open up the top of where there were big blackheads so that removing them wouldn't "squeeze" the blackhead and cause scarring around the area.
I highly recommend that you talk to your son's dermatologist about this. If there is not an esthetician on staff, they can tell you where to go. And go ahead and try the Accutane.