What are the treatment options for xerostomia (dry mouth)?

Treatment of Dry Mouth (Xerostomia)

Treatment should begin with objective measurement of salivary gland function, followed by a stepwise approach: non-pharmacological stimulation for mild dysfunction, pharmacological stimulation with pilocarpine 5 mg four times daily for moderate dysfunction, and saliva substitutes for severe dysfunction, with supportive oral care measures implemented at all severity levels. 1, 2

Mandatory First Step: Assess Salivary Function

• Measure whole salivary flow rates (both unstimulated and stimulated) before initiating any treatment, as subjective feelings of dryness frequently do not correlate with actual salivary output. 1, 2, 3
• Do not rely solely on patient-reported symptoms to guide treatment selection, as this leads to inappropriate therapy choices and ineffective management. 1, 2
• Rule out unrelated conditions such as candidiasis or burning mouth syndrome before attributing symptoms to xerostomia. 1

Treatment Algorithm Based on Severity

Mild Glandular Dysfunction (Residual Salivary Function Present)

• Use non-pharmacological salivary stimulation as first-line therapy: sugar-free chewing gum, xylitol lozenges, sugar-free acidic candies, or other gustatory/mechanical stimulants. 1, 2
• Xylitol-containing products provide dual benefits by stimulating saliva production while simultaneously protecting against dental caries. 4, 2
• No single non-pharmacological intervention has been proven superior to another, so patient preference should guide selection within this category. 1, 5

Moderate Glandular Dysfunction (Reduced but Measurable Salivary Function)

• Prescribe pilocarpine 5 mg orally four times daily (20 mg/day total) as the preferred pharmacological stimulant. 1, 2, 6
• The dose may be increased up to 30 mg/day (7.5 mg four times daily) for improved efficacy if the initial dose is insufficient and tolerated. 2, 6
• Cevimeline is an alternative muscarinic agonist with a similar mechanism but potentially better tolerance profile, though pilocarpine remains the FDA-approved standard. 1, 4, 6
• Monitor for common adverse effects: sweating (most common cause of discontinuation at 12% with 10 mg three times daily), nausea, rhinitis, diarrhea, chills, flushing, urinary frequency, dizziness, and asthenia. 6
• Exercise caution in elderly females, as they demonstrate approximately twice the drug exposure (Cmax and AUC) compared to elderly males and younger volunteers. 6

Severe Glandular Dysfunction (Minimal or No Salivary Output)

• Use saliva substitutes as the primary therapeutic approach when salivary glands lack functional capacity to respond to stimulation. 1, 2
• Select products with neutral pH containing fluoride and electrolytes to mimic natural saliva composition; available as oral sprays, gels, and rinses. 1, 4, 2
• Oxygenated glycerol triester (OGT) spray demonstrates superiority over aqueous electrolyte sprays, with approximately 2 points improvement on a 10-point visual analogue scale for mouth dryness. 5
• Methylcellulose/hyaluronate-based substitutes are preservative-free and particularly useful for sensitive patients. 2

Supportive Measures for All Severity Levels

• Increase water intake throughout the day and take frequent small sips to maintain oral moisture. 1, 4, 7
• Limit caffeine consumption, as it exacerbates dry mouth symptoms through its diuretic effects. 1, 4, 7
• Avoid crunchy, spicy, acidic, or hot foods that exacerbate oral discomfort and mucosal irritation. 1, 4, 7
• Use specialized toothpastes and mouth rinses designed for dry mouth that are less irritating and contain fluoride for additional protection. 4, 7

Prevention of Dental Complications

• Prescribe fluoride rinses or gels for all dentate patients with xerostomia to mitigate the significantly elevated risk of dental caries. 7, 2, 3
• Untreated severe dry mouth leads to dental caries and eventual tooth loss, making preventive dental care essential. 1, 7, 2
• Arrange regular dental monitoring for all patients with persistent xerostomia to detect early complications. 7

When to Escalate Care

• Refer to rheumatology when sicca syndrome features develop or when systemic autoimmune disease (such as Sjögren's syndrome) is suspected. 1, 7
• Refer to dentistry when signs of dental complications appear or for patients requiring specialized preventive care. 1, 7
• Consider inpatient care for severe cases with significant functional impairment affecting nutrition or quality of life. 1

Critical Pitfalls to Avoid

• Do not prescribe pilocarpine or cevimeline to patients with severe glandular dysfunction (no measurable salivary flow), as these medications require residual glandular function to be effective and will only cause adverse effects without benefit. 1, 2
• Recognize that saliva substitutes provide only temporary symptomatic relief and do not restore the protective immunological and antimicrobial functions of natural saliva. 8
• Be aware that the duration of effect of saliva substitutes is short due to removal during swallowing, requiring frequent reapplication throughout the day. 8
• In patients with moderate-to-severe symptoms requiring systemic therapy, hold immunotherapy (if applicable) until symptoms improve to grade 1 before considering rechallenge. 1