Pilocarpine in Treating Patients With Dry Mouth Caused by Opioids

RATIONALE: Pilocarpine may help to relieve dry mouth in patients receiving opioids for cancer therapy. It is not yet known whether pilocarpine is more effective than no further treatment for this condition.

PURPOSE: Randomized phase III trial to determine the effectiveness of pilocarpine in treating patients who have dry mouth caused by opioids.

OBJECTIVES: I. Evaluate the effectiveness of daily oral pilocarpine versus placebo in relieving dry mouth due to the ongoing use of an opioid for cancer related pain at 2 weeks by comparing proportion of patients with at least one response during the 2 week period, time of first response, and duration of first response. II. Evaluate the adverse effects of pilocarpine in these patients. III. Evaluate whether constipation, sedation, poor appetite, and nausea are ameliorated by pilocarpine in these patients. IV. Evaluate the effect of pilocarpine on quality of life of this patient group. V. Determine the timing and duration of the effect of pilocarpine in this patient population.

OUTLINE: This is a randomized, double-blind, multicenter study. Patients receive either oral pilocarpine four times daily (arm I) or oral placebo four times daily (arm II) for 4 weeks. At the end of the 4 weeks, all patients are given the option to receive oral pilocarpine. Quality of life is assessed 2 days prior to randomization, after 2 weeks of treatment, and after 4 weeks of treatment.

PROJECTED ACCRUAL: There will be 60 patients accrued into this study within 18 months.

Eligibility Criteria:
DISEASE CHARACTERISTICS: Complaint of dry mouth with ALL the following characteristics: At least 1 week in duration Attributed by the treating physician to an opioid Severity rating at least 20 mm on a 100 mm visual analog scale Must be receiving routine (i.e., not just as needed) dosing with one of the following opioids: morphine, hydromorphone, transdermal fentanyl, methadone, or oxycodone Intent to continue opioid therapy at the same or higher dose over the first 2 weeks that the patient is receiving protocol treatment

PATIENT CHARACTERISTICS: Age: 16 and over Performance status: ECOG 0-3 Life expectancy: At least 6 weeks Hematopoietic: Not specified Hepatic: Not specified Renal: Calcium less than 29.9 mg/dL Cardiovascular: No symptomatic congestive heart failure or hypotension (systolic blood pressure less than 100 mm Hg) Pulmonary: No obstructive pulmonary disease (asthma, chronic bronchitis, or chronic obstructive pulmonary disease) Other: No known sensitivity to pilocarpine No active oral candidiasis No Sjogren's syndrome No acute iritis or narrow-angle glaucoma Not pregnant or nursing Effective contraception required of all fertile patients Must be fluent and possess sufficient cognitive ability to complete quality of life questionnaires in either English or French without assistance from a caregiver

PRIOR CONCURRENT THERAPY: See Disease Characteristics Biologic therapy: Not specified Chemotherapy: Not specified Endocrine therapy: Not specified Radiotherapy: No prior radiotherapy to a field encompassing the parotid glands At least 1 week since prior radiotherapy to the chief site of pain No concurrent radiotherapy to chief site of pain for 2 weeks following randomization Surgery: Not specified Other: No concurrent tricyclic antidepressants (amitriptyline, nortriptyline, desipramine, or imipramine)