What Is It?

Xerostomia, also knows as ‘dry mouth’, is exactly what is sounds like, having a dry mouth. It is brought on by insufficient saliva to keep the mouth wet. For oral health, saliva plays an integral role in maintaining mouth pH, keeping bacteria in check, acting as lubricant, and contains minerals as well as growth factors aiding with tooth enamel growth and oral damage repair (Miller & Brennan, 2024).

What Causes It?

There are a multitude of factors that lead to this, such as stress, dry environments and excessive mouth breathing. Medication and non medicated drugs and other substances may also cause xerostomia (Rossow, 2021) as well as genetic issues. Here is a general summary of the most common caused of xerostomia.

Genetics (Salivary Gland Dysfunction)

• Salivary Gland Dysfunction (hypofunction): One of the most common genetic reason for this dysfunction is Sjogren’s syndrome (Proctor & Shaalan, 2021). This dysfunction results in the salivary secretion glands not producing enough saliva for the mouth (Proctor & Shaalan, 2021). In essence, saliva secretion levels decreasing in volume. Other disorders and illnesses that can cause xerostomia include lupus, erythematosus, thyroid dysfunction and others (Mortazavi et al. 2014)

Environment

• Dry Environment & Mouth Breathing: xerostomia occurring only at night and/or in early mornings may likely be caused from excessive mouth breathing (breathing through the open mouth) in a dry environment (Hennessy, 2024).
• Dehydration: another cause of dry mouth is due to dehydration (Mortazavi et al. 2014), occurring either during the day or in the night.

Mental Status

• Stress, Anxiety, Mental Status: feelings of stress, anxiety and other mental / emotional conditions can also lead to xerostomia, although typically temporarily. Studies have shown that increases in stress, anxiety and depression significantly relates with salivary flow rate and volume, causing xerostomia. (Gholami et al. 2017).

Substance Use

• Medication-Induced: some medications may also cause xerostomia as potential side effects (Ito et al. 2023). In residential aged care, a study found that over 95% of the elder population had dry mouth as a side effect of medication (Thomson et al. 2021). A common type of medication used, anticholinergics, was found, in another study, to cause xerostomia rates of up to 53.7% (Chapple et al. 2007). Apart from anticholinergics, there are various other medications whose side effects may result in xerostomia.
• Cannabis (e.x. Marijuana): multiple researches indicate that marijuana use leads to dry mouth, with one such study showing that 69.6% of users experienced dry mouth soon after (ADA, 2023).
• Alcohol: as alcoholic drinks are liquid, they make physical contact with with virtually all parts of the mouth, from the teeth, gums and lips, to the salivary glands. As a result, alcohol can damage the salivary glands (Bode & Bode, 1997) in charge of producing the saliva.
• Methamphetamine: commonly known as just ‘meth’, is linked to decline in salivary buffering capacity, in essence, effecting the mouth’s pH changes, causing the mouth to have a too acidic or basic environment. In a study, with many others corroborating it’s findings, it found that methamphetamine users have significantly lower saliva production and a more acidic saliva content (Rommel et al. 2016).
• MDMA/Ecstasy: similar to the effects of cannabis, this also is shown to result in dry mouth symptoms which can last for many hours (A, S., & D, J. 2016).
• Tobacco/Smoking/Nicotine: nicotine, found in all tobacco products and other substances, minimize saliva flow (Mt. Holly, 2021), dehydrating the mouth. Smoking, either tobacco or e-cigarettes, both are shown to reduce saliva flow rate as well as irritating and damaging the salivary glands (Rad et al. 2010).

It’s Effect

Xerostomia not only causes mouth discomfort due to the dryness, but it also causes oral decay. With an imbalance of pH from what is healthy, periodontal diseases fester and tooth decay, via enamel decay, occurs (Baliga et al. 2013). Additionally, saliva acts as a lubricant for chewing (Vinke et al. 2021), with a decreased rate, it increases the friction in the mouth, causing pain and damage to teeth, gums and cheek lining alike. Saliva also helps re-mineralize tooth enamel and overall oral repair (Miller & Brennan, 2024), an aspect that a decreased with xerostomia.

Treatment

Effective treatment techniques vary based on the situation such as the reason for xerostomia in the first place, and it’s severity.

For genetic and disease reasons, medication may often be prescribed to combat the symptoms and get the salivary glands to work more normally.

Dry environments can be changed, mouth breathing can be fixed with practice, and dehydration by increasing water and/or fluid intake.

If xerostomia is occurring due to an abnormal mental status, mental exercise and relaxation can be used, as well as medication based on it’s severity. Seeking professional help or therapy may be beneficial here.

If it is medication-induced, talking with a medical professional will be very useful, making sure to be open and honest about the situation and side effect. Medication may be changed to something else, or additional medication may be prescribed to combat the xerostomia symptoms.

For all other substances use (such as drugs, alcohol and smoking), it would be best to get rid of their use and/or the addiction. Depending on the severity, one may be able to stop using the substance by themselves. Otherwise, other treatment pathways are available such as medical/drug detox, inpatient rehab, and outpatient programs. These three options all center around getting rid of the substance addiction, with the difference being how they go around it. Medical/drug detox is to fully get rid of the substance from a patient’s system. Inpatient rehab will have the patient live in a rehab facility 24/7 for a short time, and outpatient programs have the patient able to live at home and go into the public. All three of these options are under the supervision of healthcare professionals, with access to various therapies to help through the rehab journey.

Take Home

Xerostomia, in a nutshell, is when there is not enough saliva available for the mouth to perform as it would under naturally health conditions, otherwise known as ‘dry mouth’. This can be caused by a variety of factors, including disorders and diseases, as well as mental status, dry environments, medication side effects and substance use.

Thankfully, not all is lost! There are many treatment options and plans for these issues. From different medication, to lifestyle changes and therapies.

References

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Bode, C., & Bode, J. C. (1997). Alcohol’s role in gastrointestinal tract disorders. Alcohol health and research world, 21(1), 76–83.

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Ito, K., Izumi, N., Funayama, S., Nohno, K., Katsura, K., Kaneko, N., & Inoue, M. (2023). Characteristics of medication-induced xerostomia and effect of treatment. PloS one, 18(1), e0280224. https://doi.org/10.1371/journal.pone.0280224

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