Thank you for your patience. There are a number of things that could be going on here, but it is quite likely that the increased urination and decreased appetite is quite different to the scratching. Hopefully LouLou is up to date with flea treatments, as even if she is a strictly indoor cat, she would still need very regular flea treatments to ensure she isn't affected by fleas. Do follow up on this and arrange flea treatment for her if she isn't up to date now. The other thing we need to consider is that she could have an overactive thyroid. This can cause scratching and skin problems, as well as increased water intake, and hence increased urination as well. Typically hyperthyroid cats eat MORE than usual to begin with, but with time they can become inappetant as well (particularly if they have concurrent dental disease).
Other causes for increased urination include diabetes, kidney disease and even cancer, so it really will be important that you get help to get LouLou seen by a local vet tomorrow if at all possible for a full check up and 'senior blood test'. This will help to identify and internal organ or endocrine issues (such as the hyperthyroisidim, diabetes or kidney disease mentioned above. You may be able to find a vet that does a house visits.
For now as your girl is only eating small amounts of baby food, please keep an eye on your girl's mucus membranes, capillary refill time and respiratory rate as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if she is continuously panting or open mouth breathing at all tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
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