When I have D, I go straight for the soluble-fiber-only diet. If I'm not totally nauseated, I do try to take my vitamins; otherwise, I just take my chewable Ca-Mg tablet which always tastes good to me.
As I've stabilized over the past couple of years, I've been able to go back to IF more quickly after a D attack. This has been possible only because I've been less C and my system has been healthier, and so I don't feel like crap for several days after an attack.
It certainly can't hurt to see if there's any very mild IF things that you can have right after a D attack. It might be cooked fruit, whole wheat bread, chicken soup with mushy veggies, or whatever seems tolerable to you at the time. But treating the C *will* help you with the D attacks in the long run!