Xerostomia: Definition, Causes, and Management

Xerostomia also called as the ‘dry mouth’, is a condition which is caused due to the reduced salivary flow in the mouth. Sometimes the salivary secretion may be totally absent. Dry mouth isn’t a disease, but a symptom, which can be caused due to a variety of reasons.

Any condition, agent or disease which causes a decrease in the salivary secretion and salivary flow in the mouth, can cause Xerostomia. In some very rare cases though, the exact cause may not be known.

Dry mouth isn’t a rare problem and is seen more commonly in people who are in their old age. It affects almost 20% of the elderly population. It is also common in people who have the habit of mouth breathing.

Although it is more commonly seen in older age, Xerostomia isn’t a part of the normal aging process.

Classically Xerostomia can be defined as the ‘subjective sensation of dry mouth, which is often (but not always) associated with hypofunction of the salivary glands’. The word is derived from the Greek language where the word ‘xeros’ means “dry” and the word stoma means “mouth”.

Xerostomia Causes: What Causes Dry Mouth?

Xerostomia may be caused due to one or more of the following reasons.

Drug-Induced Xerostomia

This one is arguably the most common cause of ‘dry mouth’ in individuals. It has been already proven that there are more than 1000 drugs which cause xerostomia in its users. These drugs belong to more than 40 categories and more than 50 subcategories. These involve both prescription and over the counter drugs.

Drugs Causing Xerostomia

Drugs that commonly cause the symptoms of dry mouth in the end user are

  • Antihistaminic drugs
  • Atropine and analogs
  • Tricyclic antidepressants
  • Antiemetics
  • Tranquilizers

Other groups of drugs that are known to cause Xerostomia are as follows.

  • Antiacne agents
  • Antianxiety agents
  • Anticonvulsants
  • Antidiarrheal agents
  • Muscle relaxants
  • Narcotic analgesics
  • Nonsteroidal anti-inflammatory drug
  • Opioid analgesics
  • Parkinson’s disease medications
  • Sedatives
  • Smoking-cessation agents
  • Urinary incontinence agents
  • Antidysrhythmics
  • Antinausea agents
  • Antipsychotics
  • Anorexiants
  • Antacids
  • Bronchodilators
  • Decongestants
  • Diuretics
  • Some High blood pressure medications

Xerostomia Caused Due To Other Diseases

Dry mouth is a major symptom in many diseases. Some of them are listed below.

  • Sjogren’s syndrome: This is the most common autoimmune disease which causes xerostomia.
  • Sarcoidosis
  • Amyloidosis
  • Rheumatoid arthritis
  • Atrophic gastritis
  • Systemic lupus erythematosus
  • Scleroderma
  • Bone marrow transplantation
  • Endocrine disorders
  • Primary biliary cirrhosis
  • Nutritional deficiencies
  • Nephritis
  • Thyroid dysfunction
  • Bell’s palsy
  • Cerebral palsy
  • Diabetes mellitus
  • Hypertension
  • Cystic fibrosis
  • Pancreatic insufficiency


Dehydration caused due to various reasons may also result in dry mouth. Following conditions may cause dehydration.

  • Diarrhea
  • Persistent vomiting or emesis
  • Anorexia nervosa
  • Polyuria
  • Reduced water intake

Xerostomia Caused Due to Cancer Treatment

One of the major side effects of the cancer treatment for the head and neck region is xerostomia. This is caused by radiation therapy. The dry mouth caused due to radiation therapy is usually an inflammatory response.

The radiation doses administered during the cancer treatment may cause the fibrosis of the salivary glands resulting in dry mouth. The severity and the reversibility of the symptom depend on the amount of radiation exposure the salivary gland has undergone. If radiation exposure is high, the resulting xerostomia may be a permanent one.

Occasionally, some drugs used as a part of chemotherapy may also result in symptoms of dry mouth.

Physiologic Causes

Sometimes certain physiological factors may also result in dry mouth.

  • Anxiety
  • Fear
  • Stress


Dysgeusia which is defined as the altered taste sensation is a condition which results from the combination of stress and xerostomia. This may be caused due to one or more of the following.

  • Stress syndrome
  • Depression
  • Zinc deficiency
  • Glossitis caused due to Iron deficiency or Vitamin B deficiency

Psychiatric Causes

Conditions like depression and hypochondriasis are also known to cause the symptoms of dry mouth.

Signs and Symptoms Associated with Xerostomia

Most common signs and symptoms associated with this condition are as follows.

  • Dry mouth
  • Halitosis or bad breath
  • Dental caries – Mostly rampant caries caused due to the partial or complete absence of salivary defense mechanism.
  • Dysgeusia – Altered taste sensation (mentioned above).
  • Chelitis
  • Ulcerations of the tongue, palate and oral mucosa
  • Oral candidiasis or thrush
  • Dysphagia
  • Fissured tongue
  • Inflammation/soreness of the tongue
  • Oral mucositis or generalized soreness/inflammation of the mouth.
  • Painful tongue, otherwise known as glossodynia.
  • Pain on swallowing
  • Speech difficulties in severe cases
  • Increased thirst


If xerostomia is associated with other diseases, the following symptoms may be obvious.

  • Dryness in the eyes
  • Blurring of vision
  • Itchiness
  • Reduced secretions in the other parts of the body like reduced vaginal secretions, low nasal and pharyngeal secretions, etc.

How to Diagnose Xerostomia?

Your dentist or doctor may perform one or more of the following investigative procedures to confirm the diagnosis if you are suffering from the symptoms mentioned above.

Sialography: This is a specialized radiograph, where a specialized radioopaque dye is injected into the salivary ducts of the major salivary glands and then an x-ray is taken.

Sialometry: This is a procedure used to measure the rate of flow of saliva.

Biopsy: This may be required when the symptoms are severe and when the other diagnostic methods haven’t produced desirable results.

Xerostomia Treatment

Completely treating the symptoms of dry mouth may not be possible in all cases. However, to find a certain level of success with the treatment, it is important to recognize the definitive reasons that are causing xerostomia and treat them if possible.

Below are some of the most common treatments that are recommended for relieving the majority of symptoms of dry mouth, if not cure it completely.

Saliva Substitutes

Using saliva substitutes is a very effective way of relieving the symptoms of xerostomia.

Saliva substitutes help in lubricating the mouth and maintaining the moisture. These artificial salivary products mimic the natural saliva.

However, they can’t stimulate the salivary glands to produce normal saliva. These saliva substitutes are available in the following forms.

  • Sprays
  • Mouthwashes
  • Mouth Rinses
  • Viscous liquids
  • Gels
  • Oils

Some of the popular saliva substitutes available in the market are mucin-based artificial saliva, Carboxymethylcellulose based artificial saliva, SalivaMax, Entertainer’s Secret spray, Glandosane spray, and Moi-Stir spray and swabs.

Saliva Stimulants

These drugs are used to stimulate the production of saliva from the salivary glands. These saliva stimulants are mainly available in the form of oral tablets. These stimulants are also available in the form of toothpaste and lozenges.

Most commonly used saliva stimulants are pilocarpine and cevimeline. Also, chewing the sugar-free gums is believed to stimulate saliva production in the mouth. This, however, doesn’t have much effect in relieving the other symptoms of xerostomia.

Pilocarpine, which is the drug most commonly used as saliva substitute, may be quite effective in treating the symptoms of dry mouth and improving the dysfunctions of the salivary gland. One major drawback of Pilocarpine is that it is not effective in treating the symptoms in the case of radiation-induced xerostomia.

Self Care

There are certain measures which you can take at home to improve the symptoms associated with xerostomia.

  • If you are a mouth breather, get that treated first. Always try to breathe from the nose.
  • Using sugar-free gums for chewing is believed to give some relief from the symptoms.
  • Sipping on fluids regularly can help tackle the symptoms of dry mouth. Try to use noncarbonated, sugar-free drinks for this purpose.
  • Avoid tobacco consumption
  • Quit smoking. Smoking can exaggerate the symptoms of xerostomia in unimaginable ways.
  • Avoid the consumption of spicy food items.
  • Avoid wearing dentures in the night, while sleeping.


Share This Knowledge With Your Loved Ones!
Medical Disclaimer

This content is strictly the opinion of the author and is for informational and educational purposes only. It is not intended to provide medical/dental advice or to take the place of medical advice or treatment from a personal physician or a dentist. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions.

The publisher of this content takes NO responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians and/or the dentists before beginning any nutrition, supplement, medications or lifestyle program.