There were some changes a few years back, and now some of their products have active ingredients other than the antihistamine, diphenhydramine (yes, I had to look that up for spelling!).
Some don't even have it.
I use the original formula, and it still works fine for me. Touch wood, since bug season is on it's way!
For dogs, just check the packaging to make sure diphenhydramine is the only active ingredient.
I think it's completely different in the UK, and Australia and NZ, so folks there might want to check the ingredients.