Dry Mouth


Dry Mouth, Xerostomia, Salivary Hypofunction, Decreased Saliva Secretion, Hyposalivation

  • Definitions
  1. Xerostomia
    1. Perceived Dry Mouth
    2. Not synonymous with Salivary Gland dysfunction
  2. Hyposalivation
    1. Decreased Saliva production
  • Epidemiology
  1. Prevalence: 10-33% in U.S.
  • Risk Factors
  1. Age over 65 years old
  2. Polypharmacy
  • Pathophysiology
  1. Saliva is produced and excreted by the Parotid Glands, Submandibular Glands and Sublingual Glands
    1. Parasympathetic System stimulates watery Saliva secretion
    2. Sympathetic System stimulates viscous Saliva secretion
  2. Saliva plays vital role in Dental Health
    1. Re-mineralizes enamel
    2. Buffers cariogenic acids
    3. Removes food residue
    4. Inhibits Bacterial growth and fungal growth (e.g. Oral Candidiasis)
    5. Prevents Tooth Decay and Dental Caries
    6. Prevents halitosis
    7. Prevents Dysgeusia
    8. Dilutes hot, cold or spicy foods
  3. Decreased Salivation (Hyposalivation) criteria
    1. Stimulated Salivation <0.5 to 0.7 ml/min or
    2. Unstimulated Salivation <0.1 ml/min
  4. Medication-Induced Hyposalivation
    1. Unstimulated Saliva flow is affected more than stimulated Saliva flow
  • Symptoms
  • Signs
  1. Hyposalivation
    1. Tongue adheres to Oral Mucosa
    2. Saliva appears frothy or stringy
    3. No significant Salivary pooling in the mouth
  2. Sequelae of Hyposalivation
    1. Smooth Tongue on dorsal surface (filliform papillae atrophy)
    2. Fissured Tongue
    3. Oral Candidiasis (Thrush)
    4. Dental Caries
  • Management
  1. Stop, decrease frequency or decrease dosing of offending medication (typically Anticholinergic drugs) as much as possible
    1. See Medication Causes of Dry Mouth
    2. Avoid Alcohol and Caffeine (Diuretic activity)
    3. Avoid Tobacco
  2. General Measures
    1. Sip water throughout the day
    2. Consider a house humidifier in dry climates and seasons
  3. Saliva stimulation
    1. Sugar-free chewing gum (esp. Xylitol containing gums, but warn regarding gas, Diarrhea)
    2. Lemon lozenges
  4. Saliva Substitute
    1. Commercial Saliva substitute such as Biotene or Hydral (typically carboxymethylcellulose, mucin or Glycerine)
    2. Products vary regarding flavor, applications and consistency
      1. Consider sprays for frequent daytime use
      2. Consider gels that coat the mouth for overnight use
  5. Dental Protection
    1. Directly apply fluoride to teeth and in Toothpaste
      1. Use 1.1% Fluoride gel daily
      2. High-Fluoride toothpaste
      3. Fluoride oral rinses
    2. Scrupulous dental care is essential
      1. See Dentist regularly
  6. Consider Muscarinic Agonists in severe refractory Xerostomia (e.g. Sjogren's Syndrome)
    1. Pilocarpine (Salagen) 5 mg tablets orally dissolved on Tongue four times daily
      1. Associated with Cholinergic, parasympathetic adverse effects (e.g. sweating, Dizziness)
    2. Pilocarpine Eye drops 4%
      1. Use two drops in a small amount of water, swish and spit four times daily
      2. Associated with fewer side effects than oral tablet preparations
    3. Cevimeline (Evoxac) 30 mg orally three times daily
      1. May be better tolerated than Pilocarpine
  • Complications
  1. Dental decay and Dental Caries
  2. Thrush
  3. Dysphagia
  • References
  1. (2022) Presc Lett 29(9): 51
  2. Daniels in Goldman (2000) Cecil Medicine, p. 2245
  3. Glick (2020) Am Fam Physician 102(10):613-21 [PubMed]