Hello again and thanks for waiting.
I have worked out an answer for you ...
Unfortunately weight loss and drinking excessively such as you describe would always be a cause for concern in the dog, the chances are some disease process is causing these symptoms. What I will do though is to talk you through just some of the possible causes of excess drinking [ polydipsia ] that I know. This is the personal list I use when presented with a dog like yours, the chances are that the disease your dog is suffering from is here somewhere
1. Diabetes mellitus - sugar diabetes - easy diagnosis via blood test
2. Diabetes insipidus - rare but does happen - catches vets out !
3. Kidney problems - diagnosed by blood tests
4. Chronic hepatitis - diagnosed via blood tests
5. Cushings syndrome
I know this may not be what you want to hear but since there is such a range of diagnosis the only advice I can give you is that you should have your dog checked over by your vet sooner rather than later. There is rarely any scope for home remedies in this sort of situation. A quick blood test will very often shed light on the matter.
Sorry I cannot safely suggest any simple home remedies via the internet.
I hope I have covered your question fully enough but if you would like further clarification or to talk things over a bit more then I will be on-line for the next hour or so and I will be more than pleased to continue working with you.
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