lethargic, not eating but not in distress and vet is stumped? or what's your cat's favourite food

[tharsheblows]

First: I've taken him to the vet who looked him over thoroughly then did a full series of blood tests which didn't show any issues, except that he's lost a ton of weight quickly. His teeth are not great but not horrible. My poor cat HATES the vet and attacked them when they took the blood so the vet and I decided he was better at home as he had no chance of getting better there over the weekend. (He is the sweetest and most cuddly cat at home!)

BUT! He's not eating at all and is somewhat lethargic. He's drinking a bit but goes and looks at and sniffs his food then blankly looks away uninterested. He's also not himself at all, he seems kind of confused and forgetful and just spacey, like he's not sure where he's supposed to be or what he's supposed to be doing.

He's not vomiting that we can see and he doesn't have diarrhoea (he's an outdoors cat so it's unsure but none that we can see there either) and he's not in any pain and doesn't seem uncomfortable. He purrs when I pick him up and still comes up to sit on my husband or me when we're watching tv and sleeps with us.

Has anyone else had this with their cat? What was it? He's around 12 years old we think. He was a starving stray when he showed up 10 years ago, I had a thread about it at the time as I wanted to make sure I wasn't accidentally stealing someone's cat.

Also, what's your cat's favourite food? His is (used to be?) tuna but that is not working at all. I'm willing to try anything at this point.

My cat had a spell of not eating favourite her food. I went to my local Sainsbury’s and picked up several little tins of different brands of food.
Happily it whetted her appetite, I think one of them was a sloppy little gourmet tin, not something she usually has.
Funnily enough she isn’t eating properly now, I’m throwing most of her food out but I’m assuming someone else is feeding her rather than illness because she hasn’t lost any weight.

I hope you manage to find something that your cat finds appetising soon - such a worry.

Thank you! I will do that. He has a wide variety but maybe just tired of the usual suspects?

My husband did get him to eat cooked chicken breast, hand fed and with encouragement. Not a sustainable solution but fingers crossed it's the beginning of it getting a bit better!

When my cat would not eat he eventually ate hand fed wafer thin ham from D's. After about 8 or 9 days he perked up. Now he is eating well again. My cat had nose sniffles so wondered if he could not smell. Smell linked to appetite in cats.

Have you tried adding tuna water to his food?

I'm so sorry I didn't come back! He's eating again!

@caringcarer it seemed like he couldn't smell -- I asked the vet and he basically dismissed it but I still think he couldn't smell his food and, because he's not the world's brightest cat, didn't realise his food was his food.

I also bought wafer thin ham (oh the memories of packed lunches) @caringcarer and a bunch of single packet food for taste tests, thanks @10001namechanges! He likes some I didn't think he'd like.

I'm saving his tuna water too @fairylightsandwaxmelts. :)

So I've taken all your suggestions, thank you! It's just that I forgot to come back and update.