You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Psychogenic polydipsia has been described in humans and dogs - most often Boxers and German Shepherds

The characteristic finding in dogs with so-called psychogenic polydipsia is that the animal drinks a large volume of water then it eliminates it as urine some time later- so the polyuria is secondary to the polydipsia. This is different to other causes of polydipsia/polyuria because the polydipsia is usually secondary to the polyuria.

In humans psychogenic polydipsia is associated with disorders of the thirst centre in the hypothalamus of the brain. The same may be true in dogs, but currently veterinary authors consider the compulsive drinking behaviour in dogs to be a habit. Affected dogs often have what owners describe to be a "neurotic temperament" and the binge-drinking occurs following a stimulus such as the owner leaving the house, or the owner arriving home. 

These dogs usually drink a lot of water when the owner is at home, and may drink nothing when the owner is absent. In addition, the animal may drink normally when it is in kennels or another environment such as a neighbours house or a veterinary surgery premises. So, observation of the animals drinking behaviour by the owner is very important to aid in reaching a diagnosis, and the dog may not show the typical signs of the disorder at all during periods of hospitalisation. 

Treatment can be achieved by gradually restricting access to water - it is suggested that water volume be reduced by 10-35% every week. However, if the excessive drinking is simply a manifestation of another behavioural disorder - such as separation anxiety, the dog may begin to show other abnormal behaviour patterns such as continuous barking or chewing furniture instead.

Some authors have recommended supplementing the dog with sodium (1g/30 kg body weight) to compensate for any losses due to "medullary wash-out" - however, increasing sodium (salt) intake increases thirst, so this might mask the underlying desire for water.

Updated October 2013