The cholinesterase inhibitor physostigmine for the local treatment of dry mouth: a randomized study.

Application of physostigmine to the oromucosal surface with the aim of stimulating underlying mucin-producing glands while reducing cholinergic systemic effects might be a strategy for treating dry mouth. Subjects suffering from dry mouth and with hyposalivation participated in a crossover, double-blind, randomized study. A gel containing physostigmine (0.9, 1.8, 3.6, and 7.2 mg) or placebo was applied to the inside of the lips and distributed with the tongue. The feeling of dryness was assessed using a visual analogue scale (VAS) (where a score of 100 = extremely dry) and systemic effects were registered. Based on assessments of efficacy and safety, the dose of 1.8 mg of physostigmine was selected for use in the second part of the study to make objective measurements of saliva volumes. Physostigmine (1.8 mg) produced long-lasting (120 min) relief (evident as a score reduction of 25 on the VAS) in the feeling of dryness. Judging from AUC values related to baseline over 180 min, the improvement for both mouth and lips in response to physostigmine was six times greater than that to placebo. At higher doses of physostigmine, gastrointestinal discomfort predominantly occurred. The volume of saliva collected in response to physostigmine was five times higher over 180 min than that collected in response to placebo. Physostigmine, applied locally, therefore appears to be a promising modality for dry-mouth treatment.

RCT Entities:   Population Interventions Outcomes