Plants poisonous to dogs
I previously asked whether penstemen is poisonous to dogs. Answers posted referred me to the excellent ASPCA reference, which I actually had already checked prior to posting my question. I posted the question because neither their "poisonous" nor "non-poisonous" list includes penstemen. I'll continue to check with other animal poison control sites and monitor this Gardening website to see if anyone else has other ideas,.
I assume you've talked to your vet, the person who will have the most up-to-date info. I was able to find this reference: http://www.wildflower.org/expert/show.php?id=12470