Effect of 1% malic acid spray on diabetes mellitus-induced xerostomia: A randomized clinical trial

Objective To evaluate the effectiveness of topical sialogogue spray containing 1% malic acid in the treatment of xerostomia in patients with type 2 diabetes mellitus. Material and Methods A randomized double-blind controlled clinical trial was conducted on 52 patients with type 2 diabetes mellitus suffering from xerostomia. Patients were assigned equally to test group who received a topical sialogogue spray containing 1% malic acid and control group who received a placebo spray. Both groups were instructed to use the spray on demand for 2 weeks. The Summated Xerostomia Inventory-Dutch Version questionnaire (SXI-D) and the unstimulated salivary flow rate were evaluated for all patients at baseline, 2 and 4 weeks after malic acid/placebo application. Results At 2 week's follow-up, the unstimulated salivary flow rate increased significantly from 0.059 +/- 0.024 to 0.191 +/- 0.064 and from 0.055 +/- 0.026 to 0.078 +/- 0.032 for test and control groups, respectively, with a statistically significant difference favoring the test group. SXI-D scores showed a significant decrease from 10.73 +/- 2.22 to 8.38 +/- 2.28 in the test group (p < 0.05), while in the control group it decreased from 10.62 +/- 1.75 to 10.23 +/- 1.48 (p > 0.05). Conclusion A sialogogue spray containing 1% malic acid increased the unstimulated salivary flow rate in patients with type 2 diabetes mellitus suffering from xerostomia.