Science Diet Cat Food Vomit

My 15 1/2 yr old tabby Has been vomiting like 3-6 times in the last 3 days.?

Today he Had Vomited White Foamy stuff. I feed both of my cats Hills Science Diet, Chicken & Rice, Dry food. I think maybe he’s either really sick or he is dying. If anyone out there has experienced something like this please let me know, or if someone knows whats wrong with him.
Thanks
Oh, by the way my cats are indoor cats NEVER GO OUT!

see that your cat is older it could be just that he is starting to shut down. take him to a vet as soon as possible would be my advice. if he is beginning to simply just get old and his body is wearing down, he shouldnt be left to do it in pain.

(no its not a happy ending but id say its the best choice to get him a check up)

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