Orange matter in throw-up

My male cat has been sneezing a bit.  Our other cat had respiratory problem and was on antiboitics, so I went to vet and got one for the older cat. Before I gave him any of it, he threw up, twice.  The vomit looked like orange pieces of sponge, all the same size.  He has not eaten a sponge....what could this be?

I'm not sure what it could be but you should definitely follow up with your vet. Especially considering you were just there they may be able to give you some advice over the phone. 

Good luck!