Old cat eating too much

My 21 year old cat is always hungry, so much, that he will eat a full pouch of food and within half an hour is asking for more. This is constant, following us to the kitchen, begging for food, eating anything he can get his paws on. I know he isnt hungry, and we have wormed him, checked with the Vet how gave hiim thyroid medicine 5 months ago, but he is still eating. He can go through as many as 4 pouches in a day, but if I dont feed him, he crys all the time, yowls and will steal food from the kitchen something he has never done before. Could my cat have Feline Dementia, forgetting he has eaten, and if so, what can I do about it? Please dont ask me to go back to the Vet as they just want to take more tests and as he is 21, I dont want to subject him to invasive things if he doesnt need to.

Hello!   There are some things here that you don't explain;  Has your cat been tested for hyperthyroidism and found to have it?   If so, then treatment will need to be given on time as prescribed in order to make the symptoms go away.  I, for example, have a different hormone dysfunction:  I am diabetic.  I need to have insulin every day.  If I take insulin for a few weeks and then stop, my blood sugar will simply rise again.  Hyperthyroid tablets are like insulin;  they do not cure the problem but help to control the symptoms.  If the symptoms are to be controlled, then medication will have to be given.  It happens to be true that the more hyperthyroid a cat, the harder they are to tablet (it makes them hyperactive and reactive, with a racing heart).  Therefore sometimes, once treatment is on board and working, then the patient will become easier to tablet.  Furthermore, daily tableting is no longer the only way to treat a hyperthyroid cat.  If you explain your difficulties to your vets, then you will find that other forms of treatment may be available.

I don't agree with the hypothesis that a cat could be so forgetful that they forget that they have eaten (more than, say, once or twice).  I have a certain knowledge of people with short-term memory loss who do this a little (e.g. take a seventh or eighth chocolate) but have rarely seen it with full meals.  This is because having no memory of eating is not the only trigger telling a person or cat to eat;  we also feel intrinsically full when our blood sugar increases, which your cat does not appear to be doing.  It is more likely that there is something else causing the symptom, for example hyperthyroidism (which your cat may be testing positive for) or cancer.

Yes, my cat has hyperthyroidism and is medicated twice daily and has been for the past 5 months.  He was recently rechecked by the vet a few weeks ago and the thyroid is working well now, with the medication, so we know it isnt that.  I buy good quality food which is supposed to be for the older cat, and I spend a lot of time with him to make sure he isnt bored, or stressed.  I am at my wits end to know what to do with him.  The food obsession is just like having a dog in the house, the begging, the stealing etc. I have done everything that has been advised and yet he is still hungry.  If it is dementia, do you know how I should deal with it?

I hear your concern that 'I do not want to subject him to invasive tests he has no need for.'  However, imagine if your food was not 'touching the sides' and you felt permanently hungry, however much you ate.  This is not pleasant for a cat to live with and it sounds as though the cat may be suffering.  I do feel that a return to your vet, or a different vet (they will usually get the notes e-mailed across) for diagnosis if necessary and then either treatment or euthanasia, may be the most compassionate way forward.

Hello!   Sorry  I didn't get that last message through.   So:  it sounds as though hyperthyroidism is not the cause of the problem.  Sorry - I hadn't appreciated that at first.  More coming.....

I have never seen that sign attributed to dementia alone, for the reasons I described about the body feeling full when it is full, whether we can remember how we became full or not.  "Dementia" is not fully recorded in cats although similar signs have other names.  This leaves me wondering whether the thyroid has changed since the previous test, or whether a second disease is in play here.  Possible second diseases may include liver disease, cancer, diabetes, a brain tumour etc.  More following.....

Practically speaking, good questions for your vet would be:  What could be causing this combination of signs?   What would we do about each of these if we found them?   You could then look through these possibilities and treatment and make a decision as to whether it feels appropriate for you and your cat to diagnose any of them.  If not, then the follow-up question may be 'Do you think that my cat would be suffering if I did nothing?' and perhaps to consider the future from there.