Results
In Group A (n=8), where the rats were subjected to transtympanic instillation of 25% ethanol henna extract, no vestibular dysfunction was observed at 4 hours, 24 hours, 48 hours, 72 hours, one week, two weeks, and three weeks post-instillation. Similar results were observed in Group B (n=8), where the rats were subjected to transtympanic instillation of 25% aqueous henna extract, and Group C (n=8), where the control group received transtympanic instillation of normal saline.
Provided the scores were 0 for the baseline and all post-test parameters (Table 1), statistical analysis could not be performed for this research.  In other words, there was no impairment of all vestibular parameters documented post-instillation of both aqueous and ethanol henna extract in the middle ear, indicating that Henna has no vestibulotoxic effects after it is administered into the middle ear mucosa.
This study used 24 Wistar Kyoto rats consisting of 8 male rats for Groups A, B, and C, with the latter serving as a control group. The rats were three months old when this study was performed and weighed between 300 to 400g each.