The purpose of this prospective study was to test whether intratympanic application of dexamethasone/hyaluronic acid improves hearing outcome in patients with pantonal idiopathic sudden sensorineural hearing loss (ISSHL), in patients with sudden deafness or sudden profound SHL and in patients with predominant high-frequency ISSHL who are refractory to intravenous steroid and vasoactive therapy. The study took place in an academic tertiary referral hospital involving 21 patients with pantonal ISSHL, 10 patients with sudden deafness or sudden profound SHL and 9 patients with a high-frequency ISSHL. Intratympanic dexamethasone/hyaluronic acid was administered in the affected ear. Hearing was evaluated by means of standard pure-tone audiometry. The differences between pure-tone hearing thresholds by air conduction before intravenous therapy and before the beginning of the intratympanic therapy, as well as before and after intratympanic therapy, were calculated. Statistical analysis was performed by means of the Wilcoxon's test for paired samples. Intratympanic injection of dexamethasone/hyaluronic acid results in a significant global (pantonal) improvement in hearing in patients with pantonal ISSHL. It also effects improvement in hearing at selected frequencies (namely at 1.5 and 3 kHz) in patients with a predominant high-frequency ISSHL and at selected frequencies (namely at 0.5, 0.75 and 1 kHz) in patients with sudden deafness or sudden profound SHL. Neither systemic nor local side effects were observed. Intratympanic administration of dexamethasone/hyaluronic acid provides a safe and efficacious therapeutic option for the treatment of patients with pantonal and high-frequency ISSHL who don't respond to intravenous steroid and vasoactive therapy.