Feeling parched lately? All of us would have experienced an occasional feeling of a dry mouth. This could be brought on by sudden physical stress or when faced with a much dreaded encounter. Other temporary causes of a dry mouth may include depression, viral infections, dehydration, reduced water intake, mouth breathing or medications.


Saliva is essential to our wellbeing.


An average person secretes about one and a half litres of saliva per day. An increase in saliva flow is often triggered by the anticipation of food (as demonstrated by Pavlov’s canine friends) since its primary role is to aid feeding by softening and digesting the food that we eat, as well as lubricates the throat for the passage of food.

Did you know that saliva confers some very important protective functions as well? Saliva contain immunoglobulins that safeguards against opportunistic infections that may affect the gums and oral mucosa. It also protects teeth against decay via its ability to buffer against transient acid attacks and helps to repair areas of initial decay through a process known as remineralization.


Why do some people feel that they have a permanent dry mouth?


It is indeed unfortunate that some people are afflicted with the feeling of having a permanently dry mouth. Dentists commonly refers to the condition as Xerostomia. It is perhaps important to note that xerostomia is not a disease but a symptom of other afflictions that causes either a change in the flow rate (quantity) and/or the composition of saliva (quality).


What are the causes of xerostomia?


The causative factors can be broadly categorized into the following:

  • Decreased salivary flow rate due to the long term use of medications which interfere with the production of saliva (e.g. anti-histamines or bronchodilators).
  • Increased excretion of water due to the long term use of medications (e.g. diuretics and caffeine) or endocrine disease (e.g. diabetes).
  • Salivary gland damage due to viral infections (e.g. mumps), autoimmune disease (e.g. SjÖgren’s Syndrome), facial trauma, radiotherapy in the head and neck region or the use of chemotherapy agents.
  • Changes in the oral mucosal lining due to nutritional deficiencies (e.g. Vitamin C deficiency), disease (e.g. Scleroderma) or lifestyle choices (e.g. smoking, use of tobacco products and alcohol).



What are the other symptoms associated with xerostomia?


Patients afflicted with xerostomia may complain of one or more of the following symptoms:

  • Feeling of stickiness or dryness.
  • Cracked lips or corners of the lips.
  • Dry, fissured tongue that appears cobblestone like in appearance.
  • Thickened consistency of saliva.
  • Difficulty in chewing and swallowing food.
  • Altered sense of taste.
  • Bad breath.
  • Burning sensation in the mouth.
  • Recurrent mouth ulcers or fungal infections.
  • Pronunciation or Speech difficulties.
  • Tooth decay.
  • Feelings of distress and depression.


How does one know if he or she has xerostomia?


The diagnosis of xerostomia lies in the determination of the underlying cause. The process would require a detailed history taking of the patient’s health status, medication use and lifestyle practices as well as a physical examination. Blood investigations and biochemical tests may be needed to rule out autoimmune diseases and infections. Other investigations such as MRI scans and salivary flow measurements may be done to assess salivary gland function.


What is the treatment for xerostomia?


The management of xerostomia often requires a 3 prong approach.

It firstly involves the diagnosis and treatment of the underlying cause. For example, in the case of drug-induced xerostomia, drug substitution, dosage reduction or discontinuation of the drug may be effective in reducing the severity of the condition.

The second prong of the treatment aims to normalize the oral environment so that the patient can continue to look forward to a good quality of life. This can be accomplished with the therapeutic stimulation of salivary flow with either medication or gum chewing, coupled with the use of artificial saliva. Patients are taught to monitor and ensure that they have a consistent intake of fluids as well as avoid eating dry food and known lifestyle factors.

Patients with xerostomia are at a significantly greater risk of developing decay around the roots of their teeth, and gum disease. Those who use dentures are especially susceptible to developing oral thrush, a fungal infection known as Candidiasis. The final prong of the treatment aims to manage and reduce such risks. The daily use of fluoride containing toothpastes, adoption of a proper personal oral hygiene technique and usage of antimicrobial mouth rinses helps to prevent teeth decay and gum disease. This must be supplemented with regular visits with your dentist for preventive care and early detection or intervention when necessary.


Preventing xerostomia.


The general rule is to keep your body healthy by ensuring adequate daily fluid intake and nutrition, good oral hygiene practices. It will be wise to avoid known lifestyle causes and limit the use of alcohol containing mouth washes and one’s caffeine intake. Mouth breathers may also benefit from the use of a humidifier in the bedroom during sleep at night.