Therapeutic role of intravenous glycerol for Meniere' disease. Preliminary results

Purpose: Osmotic diuretics such as glycerol are used for diagnostic purposes in patients with a suspect of Meniere's disease (MD). Scientific evidence in the animal model and in humans has shown that glycerol can induce a reduction in endolymphatic hydrops; however, its use for therapeutic purposes in MD has never been reported. The aim of this study was to evaluate the effectiveness on symptom control of intravenous glycerol in a sample of patients with definite unilateral MD not responsive to dietary restrictions. Materials and methods: Forty patients with unilateral intractable MD were included in the study. After audio-vestibular evaluation, patients were treated with intravenous 10% glycerol with 0.9% sodium chloride, 0.5 g/kg ml once a day for 2 consecutive days every fifteen days for six months. Vertigo attacks were evaluated before and after therapy and categorized into classes A–F according to the 2015 Equilibrium Committee criteria. Tinnitus and quality of life were evaluated through the Tinnitus Handicap Inventory and the Functionality Level Scale questionnaires. Results: Before treatment, patients had an average of 3.2 vertigo attacks/month; during the six months after treatment the average number of attacks/month decreased to 1.2 (p < 0.0001). At the end of the study period, 25 patients (62.5%) were in Class B vertigo control; 10 patients (25%) in Class C; and 5 patients (12.5%) in Class D. No patients were in Class A, E and F. No hearing deterioration was found in all treated patients. Quality of life according to administered questionnaires improved after treatment. Conclusions: In our sample, intravenous infusion of glycerol for two consecutive days every fifteen days for six months based on the patient's weight improved vertigo attacks and reduced the discomfort generated by tinnitus raising quality of life in patients with unilateral MD unresponsive to dietary restrictions.