I take 2 large measuringspoons full of Metamucil per day. One in the AM, one in the PM in 8oz of cold water.
The trick is to guzzle it quickly before it 'coagulates'. I use the orange tasting kind and find it OK to drink.
How did I know the Ileus had resolved. Lets just say it was the most anticipated fart of my life. Once I passed air I felt my insides move and started on clear liquids right away. Tolerated those and was on my way to real food very soon.
Hope your Ileus clears up quickly. Its such a frustrating waiting game.