Dry Mouth (Xerostomia): Causes, Symptoms, Diagnosis, Treatment And Prevention

Dry mouth, also known as xerostomia, is a common yet overlooked disorder of the salivary glands in which they are unable to make enough saliva to keep the mouth wet. The hypofunction of salivary glands often leads to difficulties in chewing and swallowing food, tasting and speaking. ^[1]

Saliva is considered as a vital body fluid that helps preserve the oral cavity and its functions. It is mainly a form of liquid which lubricates the mouth, helps cleanse the oral mucosa, preserves the sense of taste and protects the teeth against decay and dry mouth and neutralizes acids produced by harmful microorganism in the mouth. Thus, when the saliva production decreases due to conditions like medications and drugs, oral health is greatly affected followed by other health issues like dry mouth. ^[2]

Xerostomia is common in elder people, though it varies as per the individual's gender, age and medical condition. According to the Singapore Dental Journal, the prevalence of dry mouth is more in older women than men, maybe due to menopause and other hormonal changes. ^[3]

Causes Of Dry Mouth

There are a plethora of causes responsible for dry mouth. They are as follows:

Salivary gland infection: Certain virus or bacteria can lead to salivary gland infection resulting in inflammation of the salivary gland and reduced saliva leading to dry mouth. ^[4]

Dehydration: Loss of body fluid due to excessive sweating can lead to dry mouth. ^[5]

Mental conditions: Mental disorders like anxiety, depression, fear, distress or feeling of overwhelming can cause dry mouth. ^[6]

Medications: Over-the-counter drugs and medications for diabetes ^[7] , hypertension, muscle relaxants and pain killers can produce dry mouth as one of their symptoms.

• Stomach disorders: Bacterial diseases like cholera ^[8] and diarrhoea are also responsible for causing dry mouth as one of their main symptoms.
• Chemotherapy: Radiations of chemotherapy during cancer treatment can damage the salivary gland and cause dry mouth. ^[9]
• Liver damage: Excessive drinking can lead to serious liver disorders like liver cirrhosis which may cause dry mouth. ^[10]
• Nerve damage: When certain nerves of the head or neck are damaged due to injury or some medical conditions, dry mouth may occur. ^[4]
• Substance abuse: Consumption of marijuana, cigarette or other illicit drugs can cause serious medical conditions along with dry mouth. ^[11]
• Pregnancy and breastfeeding: Due to hormonal changes during the pregnancy, dry mouth may occur. ^[12]
• Enlarged adenoids: They are similar to tonsils and produce antibodies to fight against infections. When they grow in size due to some infection, one of the symptoms caused is dry mouth. ^[13]
• Diabetes: Uncontrollable diabetes (Type 2) can cause dry mouth. ^[7]

Other conditions responsible for dry mouth is rheumatoid arthritis, lupus, lichen planus (white-lesions in the mouth), eating disorders like anorexia and surgeries like bone marrow transplant.

Symptoms Of Dry Mouth

Symptoms of dry mouth are as follows:

• Dryness in the mouth and throat ^[1]
• Getting thirsty frequently
• Cracked lips
• Bad breath ^[14]
• Taste disorders
• Production of sticky saliva ^[1]
• Problem during swallowing, eating or speaking
• Gum problems like periodontitis or gingivitis
• Continuous cough
• Tongue inflammation ^[15]
• Dryness of eyes and nasal passage
• Ulcers in the mouth
• White tongue
• Tooth decay ^[1]

Complications Of Dry Mouth

Decreased saliva production leads to several severe complications of the mouth like the following:

• Dental problems like gingivitis, plaque and periodontitis ^[1]
• Yeast infection in the mouth
• Dry and split skin near the mouth
• Malnutrition due to the inability to chew and swallow foods ^[16]

Diagnosis Of Dry Mouth

Diagnosis of dry mouth can be easily done by a few simple tests. They are as follows:

• Oral examination: To look out for signs and symptoms of dry mouth like gum problems and tongue inflammation ^[17]
• Medical history: To find the cause behind the dry mouth by reviewing the previous medical history (if any) of the patient
• Biopsy: Here, a sample of a salivary gland is taken to identify the medical condition causing dry mouth.
• Sialometry: To measure the flow rate of saliva ^[18]
• Scintigraphy: It is another method to measure the flow rate of saliva by injecting radioactive material in the body.

Treatment Of Dry Mouth

As people with dry mouth often face oral and gum problems like gingivitis and periodontitis, they should first concentrate on maintaining dental hygiene by regular brushing and flossing. If it does not work out, a doctor may suggest for the following treatment methods:

• Changing the dose of medications: Here, the dose of certain medications prescribed to the patient for their medical condition is changed.
• Antifungal medications: To treat the fungal infection of the mouth caused due to dry mouth ^[19]
• Over-the-counter saliva substitute: Some OTC saliva substitute, also known as artificial saliva, contains xylitol or hydroxyethylcellulose which are best in treating dry mouth. They lubricate and moisten the mouth by creating a protective film. ^[20]
• Surgery: Here, a medical expert dilates ducts present in the salivary gland by surgery and remove the obstructive stone present in them.

Tips To Prevent Dry Mouth

• Do not allow the mouth to dry out; sip water throughout the day.
• Avoid breathing with the mouth as it will add to the dryness. Breath only by the nose.
• Moisturize your lips now and then to prevent cracked lips.
• Avoid alcohol or alcohol-based mouthwash. They are diuretic, means they allow water to flush out of the body more rapidly thus, increasing dehydration and causing dry mouth.
• Use a room humidifier during night time.
• Avoid eating too salty or spicy products as they increase the risk of dry mouth.
• Brush twice a day and floss after every meal.
• Visit a dentist once or twice in a year to examine your dental health.