I was hoping to hear back from you with some additional information, but I can answer your question now, and then if you need any further information, just reply back and I will be glad to continue.
Taz's drooping eyelid may be caused by a variety of conditions; he could have an eye infection or a scratched cornea and it hurts him to open his eye all the way. This symptom can also indicate a stroke, which is not as common in cats as it is in dogs, but still, he's a senior kitty, and this is possible.
The fact that he's not interested in eating and is sleeping a lot, could be due to many medical conditions to which older cats are more prone, like diabetes, kidney failure, a liver or thyroid issue. When a cat doesn't want to eat, this indicates illness or something is wrong, which must be addressed, quickly.
When a cat doesn't eat or doesn't eat properly, for even a short period of time, he risks developing a serious liver condition called hepatic lipidosis. The only way to treat this is to get him to eat again.
Due to his age and symptoms, it would be advisable to have Taz seen, as soon as possible, by a vet, for an in-person evaluation, some blood work, and then a diagnosis will be made and the most appropriate treatment will be prescribed.
I hope you can get Taz seen, right away, and all will be well!
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