Constipation is always a concern as we well know, and I am reminded of what has written that "nothing works forever" (hope I have that right). That has proven to be true even in the case of my bedridden husband.
For most of the 20 months he's been in bed, just one spoonful of Metamucil in his morning juice, mostly likely in conjunction with his almost daily large bowl of (calorie and calcium enriched) oatmeal gave good results.
Shortly after the introduction of Thick-ItŪ to his other liquids, twice he became constipated. Prunes worked, but the trouble with that was that by the time I knew it was working, he'd had too many. After the second episode of this I (apparently correctly) assumed that the thickener which was new to his diet had upset the balance we had previously had.
I wanted to avoid future cycles of this constipation/give-a-lot-of-prunes scenario, and so what is working for us now is a small helping of cooked prunes (often cooked with some other fruit) every other day. Maybe 6 teaspoons or 3 to 4 soupspoons full.
Sometimes I add his allotment of this to a "shake" where they also serve as the thickener and then I don't need to use the Thick-ItŪ with that drink.
This is working for us, so just thought I'd share.