Digestive problems like constipation, heartburn, stomach ache and flatulence. It is also used for muscular pains.
My Grandfather used to use black pepper oil for aches. My Mum will leave some in her mouth to alleviate her sore gums and clean her oral cavity out.I don’t think I could do this personally though!
There is a lot of further information on the properties of black pepper from some great bloggers and websites including: