I am not too sure if there is an answer to your concern.
I would not use the plant as a matter of precaution.
Different toxins act in different ways. Also the question of how much was consumed, the extent of sensitivity, the ability of the toxins to maintain residence in the herbivore all have a bearing on subsequent toxicity to a predator.

Here is a link that might be useful: English Ivy toxicity

I did a google search on this. One of the people posting on here (last post) apparently has tried ivy without problems. One person responding on this post said ivy was fine for frogs, but the link they posted has ivy as poisonous. It appears to be specific partly to frogs, too. However, it sounds like that person in the first link has personal experience. So, I don't know what to think.
-Jmcat

Jmcat
How about trying some other plant. Perhaps checking out where your animals come from and seeing what kind of plants there habitat has will provide some nice plants, if available.

I did some searches, and found a few plants that might work (if I can find them). The frog this would be for would be a Green Tree Frog (Hyla cinerea). Do you have any ideas?
Thanks,
-Jmcat

Jmcat,
Think you need to browse the aquatic/aquarium plant retailers sites. Here is a link to one. But you would need to google each plant of interest to be sure it will fit in your tank. At the site below stay away from the Potted Tropical plants as they all can get big even for a greenhouse! But the Paludarium plants look ok. If you are keeping your terrarium cool you may want to check out locally native wetlands plants. Be sure to check out the home page on this site-the music is cool. Costwise I would check out the local nurseries/pet stores in your area first!

Here is a link that might be useful: Only the Paludarium plants-not the others

Ok, now I'm kind of confused. Are you thinking I should try plants from the native habitat of this frog, or mostly aquatic plants, or what?
-Jmcat

Probably a combination if there is anything that will work together. There is a world of possibiilities. check the link.

Here is a link that might be useful: worlds of vivariums

Thanks. I looked at some of the pics on that link, but couldn't get to all of them. The main thing that I noticed was that most of the terr.s used pothos, which I might end up using. I think if I can easily find some of the plants that are native to this frog's natural habitat, I'll use those. Otherwise, I'll have to mix and match.
-Jmcat