Dry mouth in palliative care

A dry and painful mouth (xerostomia) occurs commonly in patients with palliative care needs and can significantly decrease quality of life. Causes of dry mouth include:

  • damage to salivary glands (by radiotherapy, surgery or infection)
  • drugs (eg tricyclic antidepressants, antihistamines, anticholinergics, opioids, gabapentin, pregabalin)
  • mouth breathing (common during the last days of life).

Ask patients about a dry mouth (the complaint may not be volunteered) and inspect the oral cavity for inflammation, debris and infection, including fungal or viral infection.

Dry mouth is managed with meticulous mouth care, including:

  • moistening the oral cavity with frequent sips (if possible) of fluids and plain water or moisturising atomisers or sprays (eg carmellose sodium spray [Aquae liquid])
  • using simple mouthwashes, such as sodium bicarbonate dissolved in warm water
  • inducing saliva flow by using fresh pineapple pieces, frozen lemon slices, frozen tonic water or chewing gum
  • avoiding tobacco and acidic beverages
  • using mouth care products (eg mouthwash, toothpaste) that are formulations of enzymes normally found in human saliva (eg Biotene, Oral Seven)Wiseman, 2006.

Mouthwashes that may give symptomatic relief of dry mouth in patients with palliative care needs include:

1carmellose sodium 10 mg/mL solution, 1 to 2 sprays into the mouth, as required carmellose sodium

OR

1an enzyme-based mouthwash 15 mL rinsed in the mouth and spat out, 4-hourly or as required1

OR

1sodium bicarbonate–based mouthwash powder, one sachet dissolved in a glass of warm water, rinsed in the mouth and spat out, 4 times daily or as required2

OR

1sodium bicarbonate powder, half a teaspoon dissolved in a glass of warm water, rinsed in the mouth and spat out, as required.

For further information about dry mouth, see the Oral and Dental guidelines. See also General mouth care in palliative care.

Carers often assume that a dry mouth and thirst indicate a need for parenteral fluid; however, in the last days of life, there is no clear relationship between dehydration and thirst. The sensation of dry mouth should be the focus of treatment, despite carers believing relief of thirst by clinically assisted hydration will relieve dry mouth. For a discussion of clinically assisted hydration in the last days of life, see Nutrition and hydration in the last days of life.

1 Various enzyme-based mouthwashes are available (eg Biotene, Oral Seven).Return
2 Sodium bicarbonate–based mouthwash powder (eg Peter Mac Mouthwash Powder).Return