I am so sorry Sebastian is not feeling well.
Excessive thirst can be caused by diabetes or renal issues. If he is having trouble breathing he must be seen by a vet. If you are afraid to take him out call a mobile vet to come to the house. Let me know if you want me to locate one for you.
In the meantime take him in the bathroom after you run a hot shower to make a steam room. Keep him inhaling steam for ten minutes. It should break up any congestion.
Pick up any dry food. Feed him pate canned or baby food chicken or turkey with no onion or garlic.
For hydration drain the water from a can of tuna and see if he will lap it up. If he does, offer the tuna.
Warm food to bring out the aroma.
For vomiting add one quarter of a ten mg pepcid (famotidine) to a tablespoon of baby food.
He may have arthritis. If so he should take a glucosime supplement.
Canned food is also excellent for arthritis as is a glucosimine supplement:
Feed him small amounts every two hours as that is the best way for his body to metabolize calories.
Please let me know how Sebastian is doing. Reply here or if you prefer we can speak on the phone.
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