Throwing up green! Help?

Lucy, my younger one is throwing up dark green. And a lot. When my husband got home last night there were large green stains of cat vomit (and yes, we've identified that it was Lucy) throughout the kitchen. She slept with me most of the night, but when I got up this morning, there was another dark green stain on the carpet in the living room.

We bought some wheatgrass for them last Saturday, and though Henry had it a lot when he was younger, I suppose Lucy wasn't used to it. Saturday and Sunday, she was throwing up bits of grass. (Henry did too, but not as much as Lucy) We should have thought to remove the wheatgrass then, but she seemed to love playing with it.

I've tried to identify if it was anything else that could have caused this, and we can't find anything else in the house that she could have consumed that would have caused this. We threw away the wheatgrass last night.

She is acting OK, though maybe a little tired. She's had a bit if water (my main concern was dehydration) and I'm not sure if she's eaten yet today, as we freefeed. I'm going to keep an eye on her today (I'm at home from work) and see if a trip to the vet is in order.

After all that, I guess my question is: does anyone here know of anything else that could be causing this and is it cause for more concern than "watch and wait to see if it's all out of her system?

Sounds like the grass. Wheat grass won't hurt them. If she's not her normal self by tomorrow, call the vet or if she starts throwing up again today call the vet.

Could she have gotten into any rat poison? If there is any chance, get her to the vet now!! If it was just the grass. you'd only see pieces of grass, food, saliva, or yellow bile....not green! But I may be wrong on that....I hope its nothing serious.

We have no rat poison here, so there's no way she'd have gotten into that (she's indoors only). What is coming up is the color of the grass, so that's why I suspect that.

She's been doing OK today...I went and got some wet food so she could get the fluids from that, and she ate it.

I'm definitely keeping an eye on my little girl. She's drinking from her fountain right now.