Hi Penguins!
I have been wondering the very same thing and have done some research and asked a few doctors. The general consensus is that the nutrients are primarily absorbed in the small intestine, so theoretically we (ileos) should be fine. Coated and time-released medications may be a problem. I was advised to, like Bain mentioned, have smaller portions - more often. Also, it's better if you sip rather than drink the smoothie, water, or any liquid. I always have 2 or 3 drinks going, interchanging water with Propel (for the electrolytes) and sometimes cranberry juice.
Bain also suggested slowing the output with crackers or cereal. I've tried a little of everything but have found that pretzels (which I don't care for) and applesauce work the best. Another pointer was, of course, Imodium or Metamucil -- up to a tablespoon in 4 ounces of water... opposite of what is prescribed for constipation. Now a week or so after my questions to the doctor, she did a blood panel and all vitamin levels were spot on!! It actually surprised me because I feel SOOOoooo exhausted.
Oh, one thought to consider is how spinach usually affects you, such as a laxative. I found that out the hard way... I went on a 5-day camping trip where a tub of red licorice was always out. I was wondering why I was having outrageous output, then DUH. I quit munching the licorice and everything went back to normal.
Now I am trying to find out how the Vagus Nerve is affected because of interrupting the digestive system :)
I'm sure you'll find your sweet spot... everyone is different.
Here's to good health! Vicki