Dry mouth and frequent urination at night can signify an underlying condition, such as diabetes, hyperthyroidism, or overactive bladder.

These symptoms may be related and share a common cause. However, they could also occur simultaneously for different reasons.

Because some potential explanations for dry mouth and urination at night require medical treatment, a doctor needs to assess the potential causes.

This article will look at the causes, symptoms, diagnosis, and treatment for dry mouth and frequent urination at night.

A woman in bed unable to sleep due to dry mouth and frequent urination.Share on Pinterest
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Dry mouth and urination at night can be bothersome. They may disrupt sleep or make it more difficult to fall asleep.

However, these two symptoms may be more than an inconvenience. Sometimes, they indicate an underlying health condition. Potential root causes include:

Diabetes can cause both frequent urination and increased thirst, which may result in a mouth that feels dry. In addition, individuals with diabetes may experience:

People with diabetes may also have nausea, vomiting, and stomach pain.

Treatment for diabetes involves diet and lifestyle changes, blood sugar monitoring, and medications.

Diabetes insipidus

Another form of diabetes that can cause dry mouth and frequent urination is diabetes insipidus. This is a rare condition affecting approximately 1 in 25,000 people worldwide. The main complication of diabetes insipidus is dehydration due to increased water loss in the urine.

While most people produce 1–3 quarts of urine a day, those with diabetes insipidus can make up to 20 quarts of urine a day.

Doctors diagnose diabetes insipidus through tests such as a urinalysis, blood tests, water deprivation tests, and imaging. Treatment typically involves drinking more liquids to prevent dehydration. A doctor may prescribe medication such as desmopressin if symptoms do not improve.

Hyperthyroidism is a condition where the thyroid gland produces too much thyroid hormone. It affects approximately 1 in 100 Americans over the age of 12.

Hyperthyroidism can lead to various symptoms, including a dry mouth and an increase in urination at night. Other symptoms may include:

  • unintentional or unexplained weight loss
  • rapid or irregular heartbeat
  • anxiety or nervousness
  • shaky hands
  • sweating and heat intolerance
  • frequent bowel movements
  • insomnia
  • a swelling in the neck, known as a goiter

Diagnosis may involve a physical exam, looking at a person’s medical history, blood tests to measure thyroid hormone levels, and imaging studies to assess thyroid gland function.

Treatment options may include medication, radioactive iodine therapy, or surgery to reduce thyroid hormone production.

OAB is a group of symptoms that affect the urge to urinate. It often leads to frequent urination, typically more than eight times a day, including during the night.

Up to 40% of the population in the United States experiences symptoms of OAB. If a person urinates a lot, they may become dehydrated, which could also lead to a dry mouth.

Diagnosis for OAB involves a thorough medical history, physical examination, and possibly urodynamic testing or cystoscopy if a doctor thinks this is necessary.

Treatment may include lifestyle changes, bladder exercises, Botox injections, medications, and in severe cases, surgical interventions.

Prostate enlargement, also known as benign prostatic hyperplasia (BPH), is a common condition in males over the age of 50. It occurs when the prostate gland grows in size, obstructing the flow of urine from the bladder.

BPH can cause a more frequent urge to urinate and increased urination at night. Individuals with prostate enlargement may also experience:

Dry mouth is not a symptom of BPH itself. However, if a person urinates too often or drinks less water to try and manage the condition, they could become dehydrated. Dry mouth could also be a side effect of some BPH medications.

Diagnosis for prostate enlargement typically involves a digital rectal exam. It may also involve urine tests, blood tests, and imaging studies such as ultrasound. Treatment options range from medications to surgical procedures to relieve symptoms and improve urinary flow.

UTIs are common infections that begin in the urethra and bladder. They occur when bacteria enter the urinary tract and multiply. While UTIs can affect anyone, they are more common in females.

The symptoms of a UTI can include:

While dry mouth is not a UTI symptom, frequent urination could result in dehydration.

As dehydration can worsen UTIs, drinking enough fluids and seeking medical treatment is important. Without treatment, UTIs can spread up the urinary tract to the kidneys, becoming a more serious infection.

To diagnose a UTI, a doctor may carry out urine tests to detect the presence of bacteria and white blood cells. In the case of recurrent UTIs, a doctor may carry out urodynamic testing or a cystoscopy. Treatment typically involves antibiotics to eradicate the infection.

During pregnancy, hormonal changes can affect various bodily functions, including fluid balance and bladder control. This can lead to increased urination, which may be worse at night. According to a small 2023 study in Turkey, some people also experience more urinary urgency and incontinence issues while pregnant.

The loss of fluids could potentially result in dehydration and a dry mouth. Other potential signs of pregnancy include:

In some cases, dry mouth and increased urination can also indicate gestational diabetes, a form of diabetes that only occurs during pregnancy.

Anyone who thinks they might be pregnant can use an over-the-counter pregnancy test or visit a doctor.

If an individual experiences persistent dry mouth and frequent urination, it is essential to consult a healthcare professional promptly. This is especially important if the person also has other symptoms, such as unexplained weight loss, fatigue, or fever.

Early diagnosis and treatment can help manage underlying conditions and prevent complications.

If a person has any of the following signs of severe dehydration along with a dry mouth, they need to call 911 or go to the nearest emergency department:

  • extreme thirst
  • little or no urine
  • fast heart rate
  • fast breathing
  • low blood pressure
  • confusion
  • drowsiness or loss of consciousness

Dry mouth and frequent urination at night can be symptoms of various underlying health conditions, including diabetes, hyperthyroidism, overactive bladder, prostate enlargement, and pregnancy.

Some of these require medical treatment. Others can negatively affect a person’s quality of life or, in the case of pregnancy, require ongoing care. In all cases, a doctor can help make a diagnosis and recommend optimal treatments.

Treatment options vary depending on the underlying cause. These interventions may include lifestyle modifications, medications, or surgical interventions to help relieve symptoms and improve overall well-being.