Drinking a Lot of Water in Dogs

Dogs will typically drink because they are thirsty. In general, a dog should drink between 20 to 70 ml/kg per day. As with people, their body loses water and they drink to replenish what was lost. Should your dog seem to drink more than the usual amount of water or do so when not being more active than usual, it can be a sign of disease. There are multiple conditions where your dog’s body will not be able to regulate the loss of water even at normal temperatures. The water lost needs to be replenished, thus your dog will drink a lot. Conditions that may cause your dog to drink a lot of water include:

• Kidney disease or kidney failure
• Diabetes mellitus
• Cushing’s disease
• Psychogenic polydipsia
• In reaction to a medication

If your dog is drinking more than usual for his size and level of activity, how serious it is will depend on its cause. Some conditions, like diabetes mellitus will be serious and require significant treatment. In others, for example when the excessive drinking is due to a medication your dog is taking, it may be less of a concern.

The reason for your dog drinking a lot will depend upon its cause. For example:

Kidney Disease or Kidney Failure

In kidney (also called renal) disease, the kidneys don’t work correctly which leads to their being unable to filter toxins out of the bloodstream as they would typically. This condition will lead to the water balance in your dog’s body being off, causing him to drink more.

In kidney (also called renal) failure, where the kidneys will no longer function, the condition can come on quickly or over a long period of time and may bring other complications with it. The acute form of the condition is usually the result of injury or your dog ingesting a toxic substance. Chronic kidney failure is more likely to occur in older dogs. Your dog’s kidneys will eliminate metabolic waste and create urine to flush the waste out. The blood that flows through your dog’s kidneys is filtered and there is a certain amount needed in the blood and an amount to be gotten rid of. 

When the kidneys are not working, the waste will build up, leading to an increase in thirst.

Treatment needs to be administered right away; typical early signs are an increase in thirst and increased urination. Your dog will drink excessive amounts of water because as the condition gets worse, his kidneys will not process toxins efficiently and more water will be needed to do the job. Despite the increase in urination, toxins won’t be eliminated as well as they had prior to the kidney disease.

Your dog may be susceptible to kidney disease as a result of underlying health issues or injury, among other reasons. 

Diabetes Mellitus

Also known as “sugar diabetes” the condition occurs when your dog’s body is struggling to connect his glucose and insulin, which are necessary for your dog’s health. When they are not working properly, diabetes is developed; the cause is your dog’s pancreas not producing insulin as it typically would. Without insulin, your dog’s body will not obtain the glucose his body requires. 

Cushing’s Disease

Clinically defined as hyperadrenocorticism, Cushing’s disease is when your dog’s endocrine glands don’t keep the necessary balance of cortisol in his body. The origin of the condition is an unusual growth of tissue or trauma in either the pituitary or adrenal glands. In Cushing’s disease, the hormone cortisol will be over produced. Usually the hormone is in your dog’s system in low levels and will elevate during stress. Its role is to help suppress inflammatory signaling and increase your dog’s blood sugar. 

Psychogenic Polydipsia

While not common in dogs, psychogenic polydipsia is a behavioral condition where excess thirst will physically manifest itself.

In Reaction to Medication

Some medication will note an increase in thirst as a side effect.

Should you notice that your dog is drinking a lot, and is not taking a medication where that may be a side effect, you will want to contact your veterinarian right away. A full physical examination will be conducted and your veterinarian will ask you for information regarding any other symptoms and/or behavioral changes you have noticed in your dog. It is likely that your veterinarian will conduct blood testing to include a complete blood count and blood chemistry profile. In kidney disease, your dog will typically show high creatinine and blood urea nitrogen in his blood. Electrolytes will also be evaluated to look for the presence of phosphate. In diabetes, high levels of glucose are typically found in the blood. Your veterinarian will consider the liver enzymes of your dog in making a diagnosis. In Cushing’s disease, the blood may show a greater than normal SAP (serum alkaline phosphatase), and increased ALT, high cholesterol, high blood sugar and decreased BUN (blood urea nitrogen). A urine sample will likely be taken and analyzed for levels of glucose that are present; high levels of glucose can point to diabetes mellitus. If kidney disease is suspected, radiographs or ultrasound may be used to look more closely at the size of the kidneys and seek an underlying cause. In some cases, a biopsy will be necessary. 

If your dog’s test results do not show abnormalities, your veterinarian will consider psychogenic polydipsia. Based on the answers to his questions, he may also consider that your dog is drinking more water as a result of salty treats or significant activity.

It is important that you provide your dog with a healthy diet that provides him with the nutrients that he needs. Regular exercise is also important for him to maintain a healthy weight and overall health. An annual check-up will allow your veterinarian to notice any developing issues and address them right away.

Treatment for this symptom can vary greatly in cost. In the case of kidney failure, costs can average around $7,000, while in Cushing’s disease the average is around $2,000. If your dog’s excessive drinking is due to a medication, there will likely be no treatment cost. Regardless of the condition, the cost will vary based upon where you live and your area’s cost of living.