A comparison of salivary substitutes versus a natural sialogogue (citric acid) in patients complaining of dry mouth as an adverse drug reaction: a clinical, randomized controlled study.

Objective: We aimed to compare the efficacy of saliva substitutes and citric acid long-term therapy for oral dryness relief and unstimulated salivary flow in patients reporting drug-induced xerostomia.

Study Design: Fifty-four patients reporting drug-induced xerostomia were randomly subdivided into 3 groups and respectively administered artificial saliva, 3% citric acid, or distilled water in mouthwash 4 times a day for 30 days. Patients underwent measurement of unstimulated whole saliva before and after they finished therapy and were asked to note in a daily diary any symptomatologic changes 15 minutes and 1 hour after each daily intake of test solution.

Results: Fifteen minutes after solution intake, 12 patients (67%) belonging to the artificial saliva group, 9 (50%) from the citric acid group, and 2 (11%) from the water group reported significant symptomatologic improvement. One hour after solution intake, 7 patients (39%) from the artificial saliva group, 10 (56%) from the citric acid group, and 0 from the water group noted significant symptomatologic improvement. None of the drugs tested affected unstimulated whole saliva flow.

Conclusions: Both artificial saliva and citric acid provided immediate relief from oral dryness. Citric acid also provided a longer-lasting feeling of oral moistness at 1 hour after use owing to its protracted activity on salivary gland function.