I have a red, itchy top of my butt crack. There are no pimples. When I scratch, I have pieces of skin that come off.

Hello! This is an area where often moisture remains, and can become irritated. Try not to scratch so as not to weaken the skin, and you can apply a protective cream (petroleum jelly like Vaseline or zinc ointment like Zincofax) 2 to 3 times a day. If after a few days it doesn't get better, there may be a fungal infection and you could then use clotrimazole 1% (such as Canesten or Clotrimaderm) over the counter 2 times a day for 2 weeks. I hope this answers your question. Please feel free to provide me with any additional information. Thank you!