Polyuria and polydpsia are the medical terms that indicate the unnatural and excessive increase in the emission of urine and the sensation of thirst that pusher drinking a lot, by causing a harmful circuit for the balance of the organism or highlighting running pathologies.
But when you need to worry when noting this not normal behavior?
The sensation of thirst is ruled by the combined work of the pituitary, a small gland inside the brain that controls the status of the hydration, the pressure and the osmolarity of blood thanks to a hormone called ADH , and of the Hypothalamus, the structure of the central nervous system located in the internal central area of the 2 brain hemispheres that monitors the concentration of the minerals of the organism thanks to a protein of the Trpv1 kind. For this reason when we introduce to many salts or sugars we need to drink more.
Also in our pets the mechanism is the same and it can cause physiological and pathological reactions.
The physiological reactions, that is a normal increase of the sensation of thirst, are given by the increase of the outside temperature above all in summer, or by the permanence in to much heated places, by the change in food from industrial to home o r from wet to dry food, or after a strong physical activity.
The pathologic consequences can be many and of different kind.
The most know are surely the diabetes mellitus, that provokes the blood glucose, and the diabetes insipidus, much less frequent, that causes imbalances of the hormones “of the thirst” and it is generally due to pituitary adenomas (neoplasias).
Also all the systemic inflammatory forms like gastritis and hepatitis provoke an increase of thirst like even the dysenteric pathologies because of the loss of liquids with faeces, or through vomit like the case of the Cushing’s disease or for increase of the a kind of hormones.
Further causes can be the Hyperthyroidism or the Addison’s disease and some kind of cancer that provoke electrolytic imbalances for the mobilization of calcium, serious infections lie Piometra, the use of many typically cortisone medicines.
In the cat the most common cause is the renal insufficiency, due to the increase of the urea reversed in the blood circulation because of the bad functioning of the renal glomerulus, the strict net of capillary tubes deputed to the filtering of the blood.
The increase of thirst is therefore a symptom that can occur in many cases, but it is not determinign to diagnose a disease.
Before alerting and advising the veterinary, we can make some assessments.
1) Since how long you have noted an irregular increase of thirst.
If the animal limits to drink water from his bowl or if he asks for running water from taps, or from any other deposit, like the water in saucers for example.
If he has been in a dehydrative phase for some time because of too much soft or diarrheal faeces.
If he has fever and he is downed.
If he feeds himself regularly or if he has frequent vomit crisis.
If, though she has finished the heat time for a while, she still has vulvar losses.
2) Then pay attention on how he urinates.
If the dog can not hold it like before and he does it at home.
If the cat makes the litter box very dirty.
In these cases it is very important to calculate the consume of water, by dosing the one drunk in 24 hours. It is not therefore allowed to drink from taps when they want, but you need to put more bowls at disposal to check the effective consume.
If the animal lives together with others, in this period o observation it is essential that he has an exclusive access to the water bowls, by settling him possibly in an isolated room.
You also need to check how much urine he makes, if the quantity is fine according to the assumed water or if it is inferior.
It is also important to collect some urine to make lab tests to verify the specific weight, the presence of hidden blood or of proteins.
At last don’t underestimate the excessive increase of the stimulus to urinate or to drink, Polyuria or Polydipsia can be very important alarm bells.