Open Access Open Badges Study protocol

Do pilocarpine drops help dry mouth in palliative care patients: a protocol for an aggregated series of n-of-1 trials

Jane Nikles1*, Geoffrey K Mitchell1, Janet Hardy2, Meera Agar3, Hugh Senior1, Sue-Ann Carmont1, Philip J Schluter45, Phillip Good6, Rohan Vora7 and David Currow8

Author Affiliations

1 School of Medicine, The University of Queensland, Brisbane, Australia

2 Department of Palliative and Supportive Care, Mater Health Services, Brisbane, Australia

3 Department of Palliative Care, Braeside Hospital, Fairfield, Australia

4 School of Health Sciences, University of Canterbury, Christchurch, New Zealand

5 School of Nursing and Midwifery, The University of Queensland, Brisbane, Australia

6 St Vincents’ Private Hospital, Brisbane, Australia

7 Department of Palliative Care, Gold Coast Health Service District, Gold Coast, Australia

8 Discipline Palliative and Supportive Services, Bedford Park, Australia

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BMC Palliative Care 2013, 12:39  doi:10.1186/1472-684X-12-39

Published: 31 October 2013



It is estimated that 39,000 Australians die from malignant disease yearly. Of these, 60% to 88% of advanced cancer patients suffer xerostomia, the subjective feeling of mouth dryness. Xerostomia has significant physical, social and psychological consequences which compromise function and quality of life. Pilocarpine is one treatment for xerostomia. Most studies have shown some variation in individual response to pilocarpine, in terms of dose used, and timing and extent of response.

We will determine a population estimate of the efficacy of pilocarpine drops (6 mg) three times daily compared to placebo in relieving dry mouth in palliative care (PC) patients. A secondary aim is to assess individual patients’ response to pilocarpine and provide reports detailing individual response to patients and their treating clinician.


Aggregated n-of-1 trials (3 cycle, double blind, placebo-controlled crossover trials using standardized measures of effect). Individual trials will identify which patients respond to the medication. To produce a population estimate of a treatment effect, the results of all cycles will be aggregated.


Managing dry mouth with treatment supported by the best possible evidence will improve functional status of patients, and improve quality of life for patients and carers. Using n-of-1 trials will accelerate the rate of accumulation of high-grade evidence to support clinical therapies used in PC.

Trial registration

Australia and New Zealand Clinical Trial Registry Number: 12610000840088.

Pilocarpine; n-of-1 trial; Palliative care; Xerostomia; Advanced cancer