Polydipsia is the medical term for excessive thirst. This increased thirst often leads to a person drinking too much water.

Drinking enough water is a healthy habit. Consuming too much, however, can be harmful and may be a sign of disease. For example, increased thirst is one of several common signs of diabetes or prediabetes. Polydipsia may provide an important clue for the millions of Americans who are diabetic but have yet to be diagnosed. Severe polydipsia may indicate serious diabetic complications such as diabetic ketoacidosis.

Polydipsia can also be due to many other conditions. These include diabetes insipidus, other endocrine disorders, dehydration, kidney disease, liver disease, urinary tract infection, mineral imbalances, head injury, drug abuse, emotional disorders and Wolfram syndrome. Certain medications can also cause excessive thirst.

Anyone experiencing persistent or unexplained thirst should discuss the matter with a physician, especially if this symptom appears with other signs of disease. For example, someone experiencing unexplained polydipsia combined with polyphagia (excessive hunger) should contact a healthcare provider.