Ethyl Loflazepate as a Treatment for Patients with Idiopathic and Psychogenic Taste Disorder

Ethyl loflazepate (EL) is a benzodiazepine derivative that has been reported to activate the gustatory cortex. Our department routinely uses EL as a first-line treatment for idiopathic and psychogenic taste disorders, although little has been reported in the literature with respect to patient outcomes, so we conducted a retrospective study examining its safety and efficacy. Between 2008 and 2020, 49 patients (14 males and 35 females; mean age, 62.1 years) were diagnosed with taste disorders and received EL as their only treatment for >14 days. Severity of taste disorder was evaluated using the paper disc method by Sakai et al [7], and treatment efficacy was evaluated using the Visual Analogue Scale, wherein patients gave subjective ratings for their symptoms (reductions by >50% after administration of EL for 4 weeks were defined as mprovements). Results showed that the improvement rates for patients with idiopathic and psychogenic taste disorders were 55% and 70%, respectively. Additionally, the majority (78%) improved within 2 weeks, and side effects were mild (seven cases of sleepiness and one case of dizziness). We conclude that EL is an appropriate first-line medication for patients with idiopathic and psychogenic taste disorders.