Gastroparesis is a very common complication of long-standing type 1 diabetes as a result of autonomic neuropathy, though for some reason there is very little discussion of it. I have it and use MDI, and I find that by having a higher than normal background dose I’m able to cover the delayed metabolism that comes with the condition. Some doctors recommend taking the meal-time, quick-acting insulin only at the end of meals rather than before the meals, though I have not found that useful. One of the silliest things gastroenterologists recommend is taking small doses of fast-acting insulin repeatedly during the day to cover the many small meals they recommend patients eat, but this really doesn’t work, since if the insulin is going to continue acting for 6 hours after each meal, it will start overlapping with the next meal’s dose and produce all sorts of confusion.
The drug, Domperidone, is perfect for controlling the disease, but some jurisdictions have banned it or severely restricted its use to short time-spans, which would make it useless for gastroparesis. The caution about Domperidone is based on its shortening of the Q-T interval of the heart beat, but the effect is in fact really minimal. It’s now unavailable in the United States, which forces patients needing it to go to Canada or the Caribbean to get it.
I have found that eating only pureed food controls the condition so well that I don’t need any Domperidone at all, and I used to have to take 60 mg a day.