Thirst - excessiveIncreased thirst; Polydipsia; Excessive thirst
Excessive thirst is an abnormal feeling of always needing to drink fluids.
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 help in detecting diabetes.
Diabetes is a long-term (chronic) disease in which the body cannot regulate the amount of sugar in the blood.Read Article Now Book Mark Article
Excessive thirst is a common symptom. It is often the reaction to fluid loss during exercise or to eating salty foods.
Causes may include:
- A recent salty or spicy meal
- Bleeding enough to cause a large decrease in blood volume
- Diabetes mellitus
- Diabetes insipidus
Diabetes insipidus (DI) is an uncommon condition in which the kidneys are unable to prevent the excretion of water. DI is not the same as diabetes me...Read Article Now Book Mark Article
- 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
Sepsis is an illness in which the body has a severe, inflammatory response to bacteria or other germs.Read Article Now Book Mark Article
- Psychogenic polydipsia (a mental disorder)
Because thirst is the body's signal to replace water loss, it is most often appropriate to drink plenty of liquids.
For thirst caused by diabetes, follow the prescribed treatment to properly control your blood sugar level.
Blood sugar level
A blood sugar test measures the amount of a sugar called glucose in a sample of your blood. Glucose is a major source of energy for most cells of the...Read Article Now Book Mark Article
When to Contact a Medical Professional
Call 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?
- Have you noticed an increased appetite?
Increased appetite means you have an excess desire for food.Read Article Now Book Mark Article
- Have you lost weight or gained weight without trying?
Unexplained weight loss is a decrease in body weight, when you did not try to lose the weight on your own. Many people gain and lose weight. Uninten...Read Article Now Book Mark Article
Unintentional weight gain is when you gain weight without trying to do so and you are not eating or drinking more.Read Article Now Book Mark Article
- Has your activity level increased?
- What other symptoms are happening at the same time?
- Have you recently suffered a burn or other injury?
- Are you urinating more or less frequently than usual? Are you producing more or less urine than usual? Have you noticed any bleeding?
- Are you sweating more than usual?
- Is there any swelling in your body?
- Do you have a fever?
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...Read Article Now Book Mark Article
Tests that may be ordered include the following:
- Blood glucose level
- CBC and white blood cell differential
A complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...Read Article Now Book Mark Article
Blood cell differential
The blood differential test measures the percentage of each type of white blood cell (WBC) that you have in your blood. It also reveals if there are...Read Article Now Book Mark Article
- Serum calcium
The calcium blood test measures the level of calcium in the blood. This article discusses the test to measure the total amount of calcium in your blo...Read Article Now Book Mark Article
- Serum osmolality
Osmolality is a test that measures the concentration of all chemical particles found in the fluid part of blood. Osmolality can also be measured with...Read Article Now Book Mark Article
- Serum sodium
The sodium blood test measures the concentration of sodium in the blood. Sodium can also be measured using a urine test.Read Article Now Book Mark Article
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...Read Article Now Book Mark Article
- Urine osmolality
The osmolality urine test measures the concentration of chemicals in urine. Osmolality can also be measured using a blood test.Read Article Now Book Mark Article
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.
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.
Mortada R. Diabetes insipidus. In: Kellerman RD, Rakel DP, eds. Conn's Current Therapy 2021. Philadelphia, PA: Elsevier; 2021:290-293.
Insulin production and diabetes - illustration
Insulin is a hormone produced by the pancreas that is necessary for cells to be able to use blood sugar.
Insulin production and diabetes
Review Date: 1/16/2021
Reviewed By: Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.