Inclusion Criteria:  unilateral vestibular hypofunction achieved according to accepted criteria, by bithermal caloric irrigation, showing at least 25% reduced vestibular response on one side when calculated by means of Jongkees' formula, 3 months or later after symptom onset. In order to avoid confounding factors, and following previous experiences, only subjects presenting with a concurrent reduction in vestibulo-ocular reflex (VOR) gain when studied by means of video head impulse test will be included in this study.  Exclusion Criteria:  History of falls, cardiovascular, metabolic, rheumatologic, orthopedic, or other neurological conditions, liver or renal abnormalities. pregnancy or breastfeeding. Neurological and neuro-psychiatric diseases insulin-dependent diabetes, vitamin deficiencies, hypothyroidism, lung diseases, hepatitis, chronic kidney failure, and Cushing syndrome medication possibly impacting on cochleo-vestibular function or with a history of drug or alcohol addiction inability to understand and agree to the examination procedures.