Excessive thirst is an abnormal feeling of always needing to drink fluids.
Alternative Names
Increased thirst; Polydipsia; Excessive thirst
Considerations
Drinking lots of water is healthy in most cases. The urge to drink too much may be the result of a physical or emotional disease. Excessive thirst may be a symptom of high blood sugar (hyperglycemia), which may be due to diabetes.
Excessive thirst is a common symptom. It is often the reaction to fluid loss during exercise or to eating salty foods.
Causes
Causes may include:
A recent salty or spicy meal
Bleeding enough to cause a large decrease in blood volume
Medicines such as anticholinergics, demeclocycline, diuretics, phenothiazines
Loss of body fluids from the bloodstream into the tissues due to conditions such as severe infections (sepsis) or burns, or heart, liver, or kidney failure
Psychogenic polydipsia (a mental disorder)
Home Care
Because thirst is the body's signal to replace water loss, it is most often appropriate to drink liquids until the thirst sensation is gone.
For thirst caused by diabetes, follow the prescribed treatment to properly control your blood sugar level.
When to Contact a Medical Professional
Contact your health care provider if:
Excessive thirst is ongoing and unexplained.
Thirst is accompanied by other unexplained symptoms, such as blurry vision or fatigue.
You are passing more than 5 quarts (4.73 liters) of urine per day.
What to Expect at Your Office Visit
The provider will get your medical history and perform a physical exam.
The provider may ask you questions such as:
How long have you been aware of having increased thirst? Did it develop suddenly or slowly?
Does your thirst stay the same all day?
Did you change your diet? Are you eating more salty or spicy foods?
Your provider will recommend treatment if needed based on your exam and tests. For example, if tests show you have diabetes, you will need to get treated.
A very strong, constant urge to drink may be the sign of a psychological problem. You may need a psychological evaluation if the provider suspects this is a cause. Your fluid intake and output will be closely watched.
References
Al-Awqati Q. Disorders of sodium and water homeostasis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 108.
Guber HA, Oprea M, Russell YX. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 25.
Verbalis JG. Disorders of water balance. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 15.
Review Date:
2/2/2023
Reviewed By:
Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.