Have Cat Questions? Ask a Cat Vet Online.
Hello. Thanks for the question.
With upper respiratory signs and vomiting, I would definitely get him to a vet. I'm sure he's going to be dehydrated and need some fluids to help rehydrate him. He will also likely need some anti-nausea meds (Cerenia, Anzemet) and potentially some antibiotics like Clavamox for the upper respiratory bug.
For now, if you want to give something over the counter to help with the nausea, there are 2 options. They can be given together if needed:
1. Famotidine (Pepcid)- 5 mg every 12-24 hours
2. Meclizine (Antivert)- 12.5 mg every 24 hours
I hope this helps, let me know if you have any other questions.