Thirst

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.

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
  

What Medications Can Cause Thirst?

Certain medications can cause thirst, including:

• Anticholinergic drugs, used to treat muscle spasms and other conditions
• Antibiotics used to treat certain infections, such as Declomycin (demeclocycline)

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:

• Blurry vision
• Fatigue
• Excessive urination (polyuria)

Summary

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.