Saliva is a watery liquid that is secreted in our mouth by salivary glands. Apart from water, saliva contains electrolytes, mucus and enzymes. It helps in binding the food that we eat and turns it into a slippery ball for an easy pass into the stomach. It also promotes a healthy oral cavity by killing the bacteria in the mouth and flushing out food debris, keeping the mouth clean.¹
Decreased production of saliva (hyposalivation), or changes in salivary composition, result in Xerostomia, most commonly called dry mouth. It is a matter of concern for oral health. While sleeping, there is a decreased rate of saliva production resulting in bad breath in the mornings. If there is not enough saliva in the mouth, it might lead to tooth decay, difficulty in swallowing, and loss of taste.
Some patients have normal salivary flow but still experience dryness of the mouth. During the episodes of anxiety or stress, a sensation of dryness occurs.
This condition significantly affects patients' health as well as their social and emotional well-being showing a negative impact on quality of life. As the cause of dry mouth is multifactorial, it is difficult to approach the condition. Many of the management options relieve discomfort by keeping the mouth moisture at an acceptable level.2
Health care providers together with patients must discuss the treatment options that are well suited for each case.
Causes of xerostomia
Depending on the duration of the symptom, the condition is specified as persistent or periodic, and based on the nature it is classified into systemic or local.²⁻³
Systemic causes are the disease conditions that are characterised by dry mouth or dryness of the eye. Sjogren's Syndrome, autoimmune disorders such as Systemic lupus erythematosus, Rheumatoid arthritis, Thyroid disease, Diabetes mellitus.
Sjogren’s syndrome is a disease affecting functions of the salivary gland. It occurs mostly in post-menopausal AFAB aged above 50 years. There is no cure to Sjogren syndrome and the goal of therapy is to manage the symptoms. It is characterised by inflammation of the salivary gland, resulting in an alteration of the production of saliva, causing xerostomia.
Dry mouth associated with primary and secondary Sjogren’s syndrome is due to the destruction of the salivary glands. One-third of the patients show enlargement of the salivary glands.
Studies have found that oral conditions are also seen in patients suffering from metabolic disorders like diabetes.¹² Dry mouth is considered a subjective complaint in diabetic patients due to disturbances in blood sugar levels.
Individuals suffering from depression or anxiety exhibit dry mouth, and the reason may be due to psychological factors or drugs prescribed for the treatment(antidepressants).
Local factors includes:
- Medication (polypharmacy)
- Cancer therapy for head and neck malignancy
Lifestyle factors include overconsumption of:
Polypharmacy is taking multiple medications due to the co-existence of two or more chronic health conditions. It is common in the older population.
Antihistamines used for allergy or asthma, antihypertensives, pain medications, and decongestants also contribute to oral dryness.⁴
Cancer therapy, with either chemotherapy or radiotherapy in patients with head and neck cancer, can change the production and composition of saliva. This may be temporary or permanent, resulting in an increased risk of oral infections.
Signs and symptoms of xerostomia
Individuals experiencing dry mouth frequently report issues such as:⁵⁻⁸⁻⁹
- Bad breath
- Stickiness in the mouth
- Constant sore throat
- Difficulty eating, speaking, swallowing
- Dry feeling in thenose
- Increased thirst
- Oral sores
- Oral fungal infection (candidiasis)
- Loss of taste
- Painful tongue
- Tooth decay
- Weight loss
- Problems wearing dentures
Management and treatment for xerostomia
Based on the cause of your dry mouth. Healthcare providers or dentists may suggest treatments to manage underlying conditions, prevent tooth decay and increase saliva flow. Your physician will have to go through all your medications if they could be causing your dry mouth and suggest an alternate medication. It will be necessary to use a combination of strategies to treat most of the instances.⁶⁻¹⁰
- Remain well hydrated and sip fluids frequently, but keep in mind that taking water throughout the day may displace your natural saliva
- Avoid sugary drinks, caffeine, alcohol, or tobacco consumption
- Avoid sticky foods like toffees or chewy sweets
- Protect dry lips by applying lip moisturiser
- Fluoride treatment is recommended to prevent cavities.
- Prompt treatment for oral infections, fungal and bacterial
- Ensure regular dental checkups
- Salivary stimulants: The regular use of sugar-free gums, mints, and candies can be used to stimulate salivary production. For patients with dental caries, avoid sugar-containing agents, Xylitol, a natural sweetener, helps stimulate salivary flow
- Secretagogue therapy: Drugs that stimulate salivation are pilocarpine (Salagen) and cevimeline (Evoxac), they provide similar benefits in patients with dry mouth. These drugs are not advised for patients with chronic asthma, glaucoma, or iritis
- Over-the-counter mouth rinses, lozenges, and gels to lubricate your lips, but also mouthwashes are remedies that alleviate dryness and also provide protection from tooth decay
- Patients must be counseled to brush and floss regularly
Dry mouth is considered a side effect for around 500 medications.³ Because many drugs have side effects, checking medication lists is crucial.
To identify salivary gland dysfunction, an imaging technique called Sialography is used.
It involves an injection of radioactive material into the glands to detect altered function.
Salivary flow rate: Tests to measure how much saliva is produced can identify the cause of dry mouth. This test is non-invasive and painless.
Biopsy: An incision is made to remove a small tissue of the glands and to test it for signs of gland inflammation.This method can be considered if the condition is caused due to other chronic health conditions, like Sjogren’s syndrome.⁴⁻⁷
Experiencing dry mouth can have a negative impact on various aspects of health. It results in poor nutrition leading to weight loss. It is a hidden cause of dental caries, gum diseases, fungal infections, cracked lips, mouth sores, and enamel erosion.3-5
Oral candidiasis is one of the common fungal infections seen in patients suffering from dry mouth. Patients must be vigilant to minimise the risks to dental health.
Therefore, maintaining good oral hygiene practices is important as it prevents complications.
How can I prevent xerostomia?
Prevention of xerostomia is not possible in all cases. But you can try drinking a lot of water, using a mouth humidifier, chewing on sugar-free gums, reducing sugary drinks, candy, alcohol and avoiding medications that can cause xerostomia like antihistamines or decongestants. Patients must consent to physicians for appropriate therapy and regular follow-up.
How common is xerostomia?
Xerostomia as a symptom is most commonly found in elderly patients over 60 years old. Although this condition is not age-related, it may occur because of medications side effects
Who is at risk of xerostomia?
Several factors can increase the risk of xerostomia (dry mouth). Some of the common risk factors include individuals with medical conditions like diabetes, HIV/AIDS, Parkinson’s, and Sjogren’s syndrome. Patients undergoing radiotherapy to the head and neck area, breathing through the mouth rather than the nose, and people who are not drinking enough water can have temporary episodes of dry mouth.
When should I see a doctor?
It is advisable to see a doctor if the symptoms are persistent. Medical attention would be appropriate if you are experiencing difficulty in speaking, swallowing, and chewing food due to a dry mouth. You can contact a dentist for tooth decay or oral ulcers to improve your oral health.
Healthcare providers can identify the underlying cause of your dry mouth and suggest various methods to manage the condition effectively.
Xerostomia, commonly known as dry mouth, is due to insufficient saliva production. The saliva helps in maintaining oral health, protects against infections, and keeps the oral cavity clean.
If there is not enough saliva production in the mouth, that can lead to a range of problems. Healthcare providers recommend lifestyle changes, adjust medication regimens, and prescribe saliva substitutes to promote saliva production. Good oral hygiene prevents oral health diseases. If you experience persistent dry mouth, seeking medical treatment is crucial as it significantly impacts your daily life and oral health.
- Tiwari M. Science behind human saliva. J Nat Sci Biol Med. 2011 Jan;2(1):53–8. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3312700/
- Kubbi J, Reddy L, Duggi L, Aitha H. Xerostomia: An overview. J Indian Acad Oral Med Radiol [Internet]. 2015 [cited 2023 Jun 28];27(1):85. Available from: https://journals.lww.com/10.4103/0972-1363.167104
- Talha B, Swarnkar SA. Xerostomia. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 Jun 28]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK545287/
- Villa A, Connell CL, Abati S. Diagnosis and management of xerostomia and hyposalivation. Ther Clin Risk Manag. 2015;11:45–51. Available from: https://pubmed.ncbi.nlm.nih.gov/25653532/
- Mayo Clinic [Internet]. [cited 2023 Jun 28]. Dry mouth - Symptoms and causes. Available from: https://www.mayoclinic.org/diseases-conditions/dry-mouth/symptoms-causes/syc-20356048
- Xerostomia – oral cancer foundation | information and resources about oral head and neck cancer [Internet]. [cited 2023 Jun 28]. Available from: https://oralcancerfoundation.org/complications/xerostomia/
- MSD Manual Professional Edition [Internet]. [cited 2023 Jun 28]. Xerostomia - dental disorders. Available from: https://www.msdmanuals.com/en-gb/professional/dental-disorders/symptoms-of-dental-and-oral-disorders/xerostomia
- Cleveland Clinic [Internet]. [cited 2023 Jun 28]. Dry mouth: xerostomia: causes and treatment. Available from: https://my.clevelandclinic.org/health/symptoms/10902-dry-mouth-xerostomia
- Xerostomia(Dry mouth) [Internet]. [cited 2023 Jun 28]. Available from: https://www.ada.org/resources/research/science-and-research-institute/oral-health-topics/xerostomia
- Dry mouth [Internet]. [cited 2023 Jun 28]. Available from: https://www.aaom.com/dry-mouth
- NICE [Internet]. [cited 2023 Jun 28]. BNF is only available in the UK. Available from: https://www.nice.org.uk/bnf-uk-only
- López-Pintor RM, Casañas E, González-Serrano J, Serrano J, Ramírez L, de Arriba L, et al. Xerostomia, hyposalivation, and salivary flow in diabetes patients. J Diabetes Res [Internet]. 2016 [cited 2023 Jun 29];2016:4372852. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4958434/