Polydipsia is a medical term that means excessive thirst. It's normal to be thirsty sometimes. You may have worked up a sweat, and your body is telling you it’s time to rehydrate. But if you feel thirsty all the time, even after drinking a lot of fluids, you may have a more serious health condition such as diabetes mellitus or diabetes insipidus.
Polydipsia is the medical definition of excessive thirst. Excess thirst is an abnormal urge to drink fluids at all times. It’s a reaction to fluid loss in your body. Dry mouth (xerostomia) and the urge to pee often (frequent urination) may go along with it.
Drinking adequate amounts of water is very important because your body needs to stay hydrated to function properly. Everyone gets thirsty from time to time. But with polydipsia, your thirst may last for days, weeks or months. No matter how much you drink, you can never seem to quench your thirst.
If you feel thirsty all the time, or if your extreme thirst has increased or continues after you drink, it may be a sign of diabetes or another serious health condition.
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Your body needs a certain amount of water to function properly. If you’re feeling thirsty, you may just need to drink more water. Your body is reacting to lost fluids. Feelings of thirst may be due to:
But excessive thirst may be a sign of certain health conditions, such as diabetes mellitus. Having higher than normal blood sugar levels (hyperglycemia) can cause polydipsia. Hyperglycemia is one of the “big three” signs of diabetes mellitus.
If you have excessive thirst and urination, but you don’t have diabetes mellitus, you may have one of the following conditions:
One of the most common reasons for waking up thirsty is you didn’t drink enough water during the day. Your body needs a certain amount of water for your salivary glands to produce enough spit (saliva). If your salivary glands don’t produce enough saliva, it can result in dry mouth. Other potential causes of extreme thirst at night include:
If you’re thirsty, your body is trying to signal that you need to replace water loss. The best way to treat this condition at home is to drink plenty of liquids. But if your excessive thirst continues, you should get in to see a healthcare provider who can determine the cause and recommend the appropriate treatment.
Depending on the cause of your condition, you may be able to prevent excessive thirst by drinking more water and other fluids. Avoid drinking caffeine and alcohol.
If you have diabetes and have access to blood glucose testing equipment, you may want to test your blood sugar levels when you’re thirsty. Testing your blood sugar levels can help you determine if your blood sugar levels are too high.
If you have excessive thirst along with the following symptoms, you should see a healthcare provider:
Your provider can help determine what’s causing your polydipsia. They’ll ask you about your symptoms and perform a physical exam. Questions they may ask include:
Your provider may also request several tests to help determine the cause of your polydipsia. These tests may include:
Based on your exam and blood tests, your healthcare provider will recommend treatment for the underlying condition causing polydipsia.
If tests show you have diabetes mellitus, they’ll recommend treatments to help manage your blood sugar levels. Treatment for diabetes insipidus may include drinking fluids to prevent dehydration. Your provider may refer you to a specialist for more specific treatments.
If your medications are causing polydipsia, your provider may adjust your dosage or change your prescription. Treatment for psychogenic polydipsia may include counseling to help you become more aware of your water consumption.
A note from Cleveland Clinic
It's normal to be thirsty sometimes. Your body may just be telling you it’s time to hydrate. But if you constantly feel thirsty even after drinking a lot of fluids, you may have a more serious health condition. See your healthcare provider to find out what's causing your excessive thirst. They can help determine treatment for whatever’s causing your polydipsia.
Last reviewed by a Cleveland Clinic medical professional on 08/24/2022.
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