Effect of 0.1% pilocarpine mouthwash on xerostomia: double-blind, randomised controlled trial

The objective of this study was to evaluate the effect of 0.1% pilocarpine mouthwash in xerostomic patients. Sixty volunteers were randomly allocated to two groups. The experimental group used 0.1% pilocarpine solution, and the control group used 0.9% saline. The short- and long-term effects of pilocarpine were investigated by measuring the severity of oral dryness, minor salivary flow rates and unstimulated whole salivary flow rate at predetermined times. The severity of oral dryness was decreased in both groups at 0, 30 and 60 min after mouthwashing, with no significant difference between the groups. Buccal and labial secretions were increased in both groups, but only the experimental group exhibited increased palatal secretion. Labial and palatal secretions, but not buccal secretion, differed between the groups. The unstimulated whole salivary flow rate was increased in the experimental group and differed from that in the control group. After 4 weeks, the severity of oral dryness was decreased in both groups and did not differ between them. The oral dryness at night or on awakening significantly decreased in both groups, with no significant difference between them, but the oral dryness at other times of the day and the difficulty in swallowing foods were not significantly changed in both groups. Minor salivary and unstimulated whole salivary flow rates did not increase in both groups. Until 1 h after mouthwashing, 0.1% pilocarpine mouthwash increased minor salivary and unstimulated whole salivary secretions, but was not superior compared with 0.9% saline at relieving subjective oral dryness.