Onset and duration of positive responses to the glycerin test in patients with Menière's disease.

The onset and duration of positive responses to the glycerin test were studied in 28 patients with Menière's disease who had positive responses to the test. The responses were measured for three hours at 30-minute intervals after the ingestion of glycerin. Positive responses were found as early as 30 minutes after ingestion of glycerin. The responses had often become negative by two to three hours. Testing of patients with Menière's disease only at the end of a three-hour interval after ingestion of glycerin will produce a large proportion of false-negative responses, as evidenced by a 39 per cent negative response rate three hours after ingestion of glycerin.