Hi Daniel
You posted this a while ago but in case you haven't done it I think you should be taking your dog along to a vet for a check up and some tests. Drinking much more than normal is one symptom that you could see with a whole range of possible internal or hormonal problems. If it's accompanied by a drop in appetite as in your dog, that's a worry or an increased appetite -that's also a worry, especially if a dog is losing weight. Is your dog losing weight? I would expect so if problems have been going on for a while. Coat changes and hair loss can be part of symptoms of a hormonal imbalance. The list is too long for me to tell you what's wrong, take her to your vet for. If you have done that you may have discovered what the problem is for her by now.
Cathy Wickenden BVet Med MRCVS
Barton Lodge Veterinary Centre
1 Midland Road, Hemel Hempstead, Hertfordshire, HP2 5BH
Tel: 01442 216048 24 hours
[
www.bartonlodgevets.co.uk]