I noticed that my old cat has not been himself. He is an outdoor cat and loves it. Hasnt been eating today though. Tonight he was hacking but nothing comes out. Also making loud swallowing sounds. He is obviously in some discomfort and i am wondering what home or OTC remedies might help. Not sure if it is hairballs. He has 1.5 inch long hair. He purs when i pet or hold him but i can tell he does not feel terrific.