What is the best medication for xerostomia (dry mouth)?

Best Medications for Dry Mouth (Xerostomia)

Pilocarpine and cevimeline are the most effective medications for treating xerostomia, with pilocarpine 5 mg three times daily being the first-line pharmacological treatment due to its established efficacy and worldwide availability. 1, 2

Treatment Algorithm Based on Severity

Mild Xerostomia

1. Non-pharmacological approaches (first-line):
   • Sugar-free acidic candies, lozenges, or xylitol
   • Sugar-free chewing gum (mechanical stimulation)
   • Improve hydration and limit caffeine intake
   • Saliva substitutes (sprays, gels, rinses) with neutral pH containing fluoride and electrolytes 1

Moderate Xerostomia

1. Continue non-pharmacological approaches
2. Add pharmacological treatment:
   • Pilocarpine 5 mg three times daily (increase to 7.5 mg if needed after 6 weeks)
   • Alternative: Cevimeline 30 mg three times daily 1, 3, 2

Severe Xerostomia (No salivary output)

1. Saliva substitution as primary approach
2. Pharmacological treatment:
   • Pilocarpine 5-10 mg three times daily
   • Consider referral to rheumatology and dentistry 1

Evidence for Pharmacological Options

Pilocarpine

• Efficacy: Significantly increases salivary flow 2-10 fold compared to placebo 4
• Dosing: 5 mg three times daily initially; can increase to 7.5-10 mg three times daily if needed 2, 5
• Onset: Rapid increase in salivary flow with peak levels maintained for 1-2 hours 4
• FDA approved for xerostomia in Sjögren's syndrome and radiation-induced xerostomia 2
• Clinical trials: Showed significant improvement in global assessment of dry mouth and specific symptoms like mouth discomfort, ability to speak without water, and decreased use of saliva substitutes 2, 6

Cevimeline

• Efficacy: 76% of patients reported global improvement in dry mouth symptoms (vs. 35% with placebo) 3
• Dosing: 30 mg three times daily (90 mg/day) 3
• FDA approved for treatment of dry mouth in Sjögren's syndrome 3
• Potential advantage: May have fewer adverse systemic side effects than pilocarpine 1

Important Considerations and Caveats

Side Effects to Monitor

• Pilocarpine: Sweating (most common, affecting >40% of patients), urinary frequency, flushing, chills, nausea, rhinitis, diarrhea, dizziness, and asthenia 2, 5
• Cevimeline: Similar cholinergic side effects but potentially better tolerated 3

Contraindications

• Use with caution in patients with:
  • Asthma
  • Cardiac arrhythmias
  • Iridocyclitis
  • Closed-angle glaucoma 7

Clinical Pearls

• No evidence of tolerance to pilocarpine has been observed during prolonged administration 4
• Patients should be warned about sweating as the most common side effect
• Significant dental complications can develop if xerostomia is left untreated, including dental caries and tooth loss 1
• For patients with combined dry eye and dry mouth (Sjögren's syndrome), pilocarpine at higher doses (30 mg/day) may also improve ocular symptoms 5
• Evaluate salivary gland function by measuring whole salivary flows before starting treatment 1

Special Populations

• In patients with Sjögren's syndrome, pilocarpine 5 mg four times daily significantly improved global assessment of dry mouth and saliva production compared to placebo 6
• For radiation-induced xerostomia, pilocarpine 5 mg three times daily produced the best clinical results when both efficacy and side effects were considered 8

Remember that pharmacological treatment should be continued long-term as xerostomia is typically a chronic condition, especially in Sjögren's syndrome or after radiation therapy.