Cat mouth foaming and vomit all over cage from car ride?

My kitty is about 10 years old. Hardly leaves the house unless going to the vet. He does have a history of Blatter crystals/obstructions. Tried to take him on a play date with friends cat plus kind of an experiment to see if I can take him with me when I move out. Currently lives with other cats his whole life. Hes... show more My kitty is about 10 years old. Hardly leaves the house unless going to the vet. He does have a history of Blatter crystals/obstructions. Tried to take him on a play date with friends cat plus kind of an experiment to see if I can take him with me when I move out. Currently lives with other cats his whole life. Hes never liked car rides like most cats screaming and crying the whole time. He got quiet for maybe 5 mins then I pulled up to friends house where I noticed him foaming out the mouth then just threw up everywhere. Immediately took him home almost back and hes crying that long meow like hes threatened by something. Is this something I should worry about? Is he just over reacting? He was really upset and did not like seeing him like that. Should also add he was panting with his mouth open. He is fine now 2 days later.
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