Hello & welcome to Just Answer/Pearl. I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.
I am sorry to hear about the issues you are having with Whiskey. When an older cat suddenly becomes restless and vocalizes without apparent reason (especially at night), there can be a reason for the behavior that has to do with the cat's health and mental status rather then truly needing our attention during those late hours.
Now we commonly find older cats demonstrating disorientation with crying/meowing (notoriously at night) when they are suffering from hypertension (high blood pressure). High blood pressure can be an old age change but can also be precipitated by underlying kidney issues, heart issues, or metabolic conditions like hyperthyroidism (one of those reasons we'd see hunger playing a role). It could also be secondary to his liver issues if the particular liver condition he suffers with is having an effect on his circulation and blood pressure. To determine if this is an issue for Whiskey, it would be a good idea to consider having his vet check his blood pressure. If it is high, there are treatments that can be used to bring this down and the vocalizing usually declines with the blood pressure getting back into normal range. Furthermore, the vet can assist you in making sure none of those interrelated conditions are precipitating his high blood pressure (either by urine or blood sample).
As well, with Whiskey's previously diagnosed liver disease, we do have to consider whether this disorientation is directly related to his liver condition. Specifically, when they have severely compromised liver function, we can see a build up of ammonia and urea (which the body would normally excrete) in the blood. This causes a condition called hepatic encephalopathy which will manifest as disorientation and even neurological signs (ie head pressing, wobbliness, tremors, seizures, etc) . So, while having his blood pressure checked, it is worth having your vet check Whiskey for any neurological abnormalities and you may even want them to re-check a blood sample to see if his liver values have worsened or if his urea +/- ammonia are elevated and thus causing these signs. If they are, the your vet can guide you on treatments to address the build up of these toxins in his blood.
Now if he does show a normal blood pressure and his liver condition is stable, then we can focus on the 'harder to diagnose' conditions that can be associated with old age. In older cats, any change in environment, and coping with his own older age (ie. sight deterioration, mental confusion, etc), can sometimes be daunting for kitties. And in these cases, he may be vocalizing because he is struggling to get used to a change. And there are things we can do to help support him with that situation as well. To give them the feeling of a peaceful safe environment, you might want to consider some de-stressing tools. Feliway, (also known as Comfort Zone in the US pet stores) is a synthetic cat pheromone that helps to soothe kitty anxiety. This can be used as a spray (that can be used on furniture or his cat bed) or a plug-in diffuser (that can be used in the room Whiskey is in most often). This may just be enough to soothe him and help him cope with being in this aged situation. There is also a diet on the market called Calm by Royal Canin. This contains a number of supplements that have been found to provide stress relief to cats. As well, there are nutritional supplements like Zylkene (which you mix into their food), which use a casein protein to soothe anxious cats.
Overall, I would advise ruling out hypertension/high blood pressure if he has started to vocalize in this manner as it is a very common cause of this behavior at his age. . Furthermore, since we know he has liver compromise, we do need to consider making sure this has not worsened to a point where toxins are building up in his blood and affecting his brain. And if we are able to clear those serious concerns, then we'd have to consider that this behavior is related to his getting older and that he may need some support for coping with his aging.
I hope this information is helpful.
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