What Is The Treatment For Itchy Shingles On The Buttocks?

is it possible to get shingles on your ( I hate to be gross) upper butt crack? Very painful and is now scabbing over. There is a line on either side at the very top...hurts to sit, etc. I work out alot and have nev er had this happen to be before. I wear poise pads becuause after two children I tend to wet myslef a little while doing cardio. Is it possible that's causing the irritation? I have been using desitin for 4 days now and it's not getting better.