Thirst is your body’s way of telling you that you need more water. It is a strong urge to drink fluids. Thirst is a common symptom that can be experienced for a number of reasons.

Common reasons for thirst include loss of fluids from the body, eating salty or spicy foods, or taking certain medications. Generally, feelings of thirst can be corrected or prevented by drinking more fluids.

Thirsty woman drinking water

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Symptoms of Thirst

When there are changes to the body's balance of water, multiple areas in the brain are activated triggering the sensation of thirst. Symptoms of thirst may include:

  • An itch in the back of your throat
  • Dryness in the mouth
  • The urge to drink liquids
  • Discomfort

These symptoms are an automatic response that motivates you to find and drink water so the balance of fluids in the body may be restored.

Causes of Thirst

Common causes of thirst include:

  • Dehydration due to hot weather, fever, exercise, sweating, or not drinking enough liquids
  • Eating, especially if the food is very salty, spicy, or sugary
  • Aromas, flavors, or other behavioral components, such as watching ads at the movie theater that may make you want to purchase an advertised beverage
  • Habits, rituals, or cravings for beverages, such as coffee or alcohol
  • Certain medications or medical conditions

Be Aware of Dehydration

Untreated dehydration can lead to serious complications if fluids are not restored. If you're experiencing feelings of thirst along with other dehydration symptoms, such as headache, fatigue, or dark urine, rehydrate with water or other rehydration solutions (e.g., Pedialyte).

If your dehydration is severe, you cannot keep fluids down, or if your symptoms don't subside with fluid intake, go to a hospital. In this instance, a healthcare professional will likely give you fluids through the vein (called intravenous fluids) to rehydrate you quickly.

What Medications Can Cause Thirst?

Certain medications can cause thirst, including:

How to Treat Thirst

The best treatment for thirst is to drink fluids, especially water. Water helps quench thirst and replenish fluids to rebalance the body. Once the water deficit is restored, the feeling of thirst should disappear.

Are There Tests to Diagnose the Cause of Thirst?

There are no tests available to diagnose thirst, but if thirst is excessive and ongoing and with unexplained causes, your healthcare provider may order tests to determine the cause. 

When to See a Healthcare Provider

If you are drinking water or other fluids regularly but you still experience extreme thirst and the need to drink more fluids than typically recommended, speak with a healthcare provider. Polydipsia, or extreme thirst, could be a symptom of a variety of medical conditions, such as high blood sugar.

You should contact a medical professional if you experience excessive thirst along with unexplained symptoms such as:


Thirst is your body's way of urging you to drink liquids. Symptoms of thirst are normal sensations that direct you to replenish your body's fluids, and should diminish once you drink more water.

Thirst can be experienced when exercising, spending time outdoors, eating certain foods, or taking certain medications. It is important to contact your healthcare provider if you are experiencing excessive thirst (polydipsia) or excessive urination (polyuria).

A Word From Verywell

More than half the human body is water and nearly every cell in the body requires water, which is why thirst is a very important sensation. Thirst helps to ensure your body has enough water for all your cells to function.

If you feel thirsty often, you may want to reflect on your daily habits and whether you are drinking enough fluids throughout the day. On a busy day, you may notice your thirst, and then realize you have only had coffee and no water. Or, you may feel thirsty after eating something very spicy, sugary, or salty. These scenarios are common and normal.

You can help prevent thirst by drinking more fluids throughout the day and with your meals—even before feeling thirsty—and drinking extra fluids if you're planning on spending time outdoors in the heat or exercising.

Frequently Asked Questions

  • How much water should I drink each day?

    Each person may require a different amount of water for their body to function at its best, but generally about 6 cups of water per day is sufficient.

    It's important to remember that water needs may increase with heavy exercise, sweating, pregnancy, and breastfeeding. If you're unsure of your water needs, consult with your healthcare team.

  • What are common signs of dehydration?

    The most common signs of dehydration in adults are:

    • Headache
    • Delirium or confusion
    • Tiredness
    • Dizziness, weakness, and light-headedness
    • Dry mouth
    • Dry cough
    • A high heart rate paired with low blood pressure
    • Loss of appetite
    • Flushed skin
    • Swollen feet
    • Muscle cramps
    • Heat intolerance
    • Chills
    • Constipation
    • Dark urine
    • Feeling cranky and anxious

    If you're feeling symptoms of dehydration, drink water or fluids to rehydrate.

  • What are ways to drink more water and improve hydration?

    Setting a daily hydration goal can help you drink more water. This can include increasing your consciousness by carrying a reusable water bottle or keeping track of how many times you refill your cup. Flavoring your water by adding fresh berries, lemon, or cucumber can help increase your water intake without added sugars (which can increase thirst).

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Encyclopedia of Human Nutrition. Perception of Thirst.
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  5. Medline Plus. Thirst - excessive.

  6. Saltmarsh M. Thirst: or, why do people drink? Nutrition Bulletin. 2001;26(1):53-58. doi:10.1046/j.1467-3010.2001.00097.x

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By Rebecca Valdez, MS, RDN
Rebecca Valdez is a registered dietitian nutritionist and nutrition communications consultant, passionate about food justice, equity, and sustainability.