Many people, may be having problems with their ileostomy--I did, I could not wear any appliance for more than a day without pain, burning, itching leakage, bleeding or skin excoriation. American doctors tend to make stomas which are too short so they may need convex flanges. Now I wear my two-piece appliance (Hollister) for a week or more.
In my case the paste(s) do not hold up to the intestinal juice attacks and simply wash away.
The solution was to cut the opening 1/4" larger as referenced (*) (**) below and to apply new Karaya gum paste 3 or 4 times a day. I will detail the procedure with pictures and instructions below. All you need is paper towels Q-Tips and a hair dryer--its easy, painless and takes less then 10 minutes. Nothing else worked for me. I spent many hours and months searching the net, testing products and many dollar$ on trials like Skin-Bond® and special ostomy seals or waifers. Now I have even gone windsurfing with my custom ostomy system, no problems no loss of optimal wear time. I have read about an ostomy patient competing in the Iron Man atheletic competitions in Hawaii; so there is hope-- just keep a positive attitude.
"If the stoma is flush or recessed, the plain MicroSkin barrier can be cut
approximately a ¼" larger than the opening and Skin Bond by Smith and Nephew can be applied to protect the exposed skin and increase the adhesion at the edge of the MicroSkin."
Modern ostomy waifers last longer than the paste due to movement of the skin and stoma and the liquid action on the paste as intestinal juice runs out. Paste may need to be replaced more often, a two piece system will allow this.