Hi Isla,
Let me see if I can unpack some of this for you. People with ileostomies are not all the same, just like all people with a certain type of cancer aren't the same. They could be Stage 1, Stage 2, Stage 3, or Stage 4 and all claim to have the same cancer. Having an ileostomy is like that, in that everyone with an ileo has a different amount of small bowel remaining. And the amount of bowel remaining is usually what determines your output frequency, all else being equal. The less bowel you have, the higher your output will be. And that's because there's less bowel to absorb what needs absorbing and less time to do that absorbing with the reduced surface area of your shortened small bowel. Every time you eat or drink something, your stomach evaluates what the fat content is of what you just put in it and determines how long it needs to stay in your stomach acid to be broken down properly before being dumped into your small bowel for absorption. Most liquids, with the exception of milk, contain little fat, so they get released into the small bowel almost immediately after they hit your stomach (because there's nothing to break down). With an ileo, you have no large bowel or colon attached, so there's nothing to absorb the majority of water when it reaches the end of your small bowel. So guess where that goes? Your liver and gallbladder make bile to help break down whatever's in your small bowel, since the stomach only breaks stuff down partially, and your small bowel only absorbs, not breaks stuff down. Your bile is reabsorbed at the very end of your small bowel in your terminal ileum. Many times when someone is given an ileostomy, the very end of the small bowel is often "involved" with whatever is causing the doctors to get your colon out of the game, so that terminal ileum that's needed to re-absorb all that bile from your liver and gallbladder is removed too. So guess where all that bile ends up?
That explains the 'liquidy' part of high output. The 'High' part is because in a normal person they have their full length of small bowel, which nature/God/whatever you believe, gave us to act as a 'buffer' so that we don't have to stop and poop every hour and get eaten by a Sabertooth Tiger or T-Rex. I know...man wasn't around when T-Rex was, but we can dream. So think of it this way...imagine a 15-foot garden hose lined with velvet...that's your small bowel. If you dump a cup of anything liquid in it, nothing will come out the other end, because the velvet will absorb it. But cut that 15-foot hose down to 5 feet and dump that same cup of water in it...and some will come out the other end. And if you dump a second cup of water in it before the first cup is fully absorbed...a lot will come out the other end. And since your small bowel doesn't absorb water (that's the colon's job), every time your stomach dumps anything liquid into your small bowel...it's flowing into a fully saturated garden hose of a bowel...so you know where it ends up. The same place as all that bile you can't recycle...in your bag. So the more small bowel you have, the longer your garden hose and the more you can put in one end before it comes out the other. That's why an ileostomate who's only missing 6 inches of his terminal ileum is very different from an ileostomate that lost 4 feet of their small bowel...but they're both "ileostomates".
So what's a girl to do! Well...it depends on how much small bowel you have left. As some have said, fiber can be your friend. But not for all ileostomates. And fiber comes in two flavors, soluble and insoluble. Insoluble needs to be avoided. We're talking about the things you're just not going to break down and digest...like seeds, fruit and veggie skins, corn, pennies, and dimes, etc. You can find a list of insoluble fiber online easily. Soluble fiber kind of turns to mush and absorbs water. So that sounds good, but remember the short garden hose. The more you put in...the more comes out the other end. And soluble fiber expands as it absorbs water, so those two tablespoons of Metamucil you just mixed up in some water will end up expanding and making more output than if you just drank the water by itself. And more output doesn't help the situation. So while soluble fiber absorbs water...which is a good thing...you're adding bulk (more output) when you use it. This is less of a big deal with the more small bowel you have. There are some on here with their full small bowel intact that claim to have pretty normal output...and that makes sense. Then there's people like me who are short-gutted, such that if I get careless and drink a lot on a hot day can end up emptying my bag 40 times in 24 hours.
Motility meds also were mentioned...and they help. Again the more bowel you have to control...the better they work. So the bottom line here is you first need to understand what small bowel length you're working with. If your surgeon was competent, it should be in their surgical report, which as a nurse I'm sure you know how to get. Then it's a balancing act of what to eat and when, combined with controlling your liquid intake. That's a whole other subject unto itself, but WHAT you drink is critical too, as the small bowel can be 'tricked' to absorb water if what you drink is the right combination of water, sodium, and glucose. But if you drink the wrong combination, your small bowel will try to make it right by pulling what's missing from your body to try to make that liquid right...and drain you of valuable sodium, glucose, or water in the process. So it's complicated, but not really. Experiment and see what works for you, and if you understand the process that I just described (in a very truncated fashion)...it will all start to make sense. And once it makes sense, you stop being a bystander just watching stuff happen...you begin being in control of what happens. And that's a very good position to be in.
;O)
PS...And just when you think you have it all figured out, you'll realize you've overlooked the fact that your remaining small bowel continues to adapt to try to compensate for what was removed. And this goes on indefinitely...but it's a good thing, as it's trying to normalize a very abnormal situation. But just something to consider as time goes on.