I recently had a problem keeping oxycontin in my system while prepping with Trilite solution before a colonoscopy. I tried to time my dose as directed-"ONE HOUR BEFORE OR 1 AND A HALF HRS. AFTER" taking both halves of the solution as prescribed but they zoomed right out of me so by the time I had the scope I was well in withdrawal. I take 40 mgs every 8 hours. Does anyone know another method that works? The Trilite is merciless and I have to do this once a year. Thanks for answering.