Megacolon question--multi cat household

Baby May has Megacolon.  She has medication for that, and has been doing very well on low residue food for two years now, but suddenly BOTH have stopped working.  Miralax does NOTHING for her, so we use lactulose (which she HATES).    The vet suggested we try her on a grain free diet, which we started today.  She said they've had decent luck on this with megacolon, but it's not a "full fix."  HOWEVER,  since we're a multi-cat household, I'm wondering how a reasonably HEALTHY cat fares on grain free food.  

Can anyone comment on EITHER the success/failure of grain free on megacolon?

Can anyone comment on the efficacy/health of a well cat with grain free diet? 

Thanks to all.

I can comment on grain free for healthy cats.  If you've been noticing foods in the pet stores, MANY of them are now stating "grain free" because that's what people want.  The reason....cats really don't need grains, so people want foodd that doesn't contain grains for their cats

Cats are obligate carnivores, meaning the need meat, not grains, or even fruits and vegies. 

Maybe this article will help you out a little bit:  http://www.thecatsite.com/a/grain-free-cat-food-what-does-it-mean

Hopefully these changes will work for Baby May.  I think they'll be good for your entire crew

Thanks for chiming in.  I didn't want to give all the girls grain free if it wasn't ok.  May did poo today, but not as much as I had hoped.  It always takes her awhile to get "unplugged."  She does seem to enjoy the grain free, though.  Both of the inside girls liked the grain free dry, which surprised me.  They're usually pretty picky about dry food.  I'm keeping a running list of the brands that they like better in wet. Regardless, the other inside cat seems unaffected by the grain free in any adverse way.  I was fearful of diarrhea or vomiting, but so far so good for the healthy inside cat, which is good.  Baby May just needs to get "passed" this.....no pun really intended. 

UPDATE:  Baby may finally FINALLY pooped.  It's been at least 4 days, but the grain free and lactulose seems to have finally kicked in.  HUGE and lots of it, but it was formed and relatively soft.  I'm going to have to locate a steady supply of PATE grain free, though.  She doesn't eat anything but pate, picky thing.  I'm just thankful for a poop finally!!  Taking it one day at a time.

Glad it's working for her.  There are lots of grain free pates  Even Fancy Feast CLASSICS are grain free.  My very picky eater really likes Nutro Natural Choice, which comes in soft loal, "chunky", which is actually a pate with a few chunks in the pate, and then minced and slices for those who will eat those. It all just depends on what your cats like, and what your budget allows for.

I had been feeding FF Classic for a long time, but didn't know they were grain free.  THAT makes perfect sense!!  Baby May stopped eating FF for some strange reason, so I grabbed a few cans of Friskies at the grocery to tide her over (not thinking about her poop habits--I know bad cat mommy).  THAT was probably what messed her up in the first place.  She is not eating much now either, but she's at least eating enough to poop.  It's also getting hot here and she doesn't eat much when it's hot out, so it's hard to judge now.

THANKS for sharing that with me.  

I also had forgotten about Nutro.  The vet suggested that name, and I forgot to look for it.  She said it's hard to find around here, but I should be able to order it online.  (I live VERY rurally with few choices, which is why I'm trying the Tractor Supply brand).

You guys are SUPER!! Thanks so much.