The aim of this study was to determine the effects of various treatment modalities employed for patients with sudden sensorineural hearing loss (SHL). We retrospectively evaluated the records of patients treated in the sudden hearing loss section of the Otolaryngology Department at Clinic Hospital, School of Medicine, University of São Paulo, Brazil, between 1996 and 2006. Our study included patients with SHL of sudden onset (occurring over a 72-hour period) at equal to or greater than 30 dB at three consecutive frequencies. We divided patients into five groups by profile and treated them with dextran, dexamethasone, acyclovir, nicotinic acid, and papaverine hydrochloride (with or without vitamin A). We performed audiometry at baseline and on days 30, 90, 120, and 180 of treatment. We determined outcome as the difference between day-0 and day-180 pure-tone averages (PTAs). Among the 139 patients evaluated, baseline PTA was similar in all groups. We observed significant improvements in PTAs after 180 days of treatment and noted a significant linear correlation between time from SHL onset to initial visit and recovery. However, no significant difference was evident among the treatment groups. In the treatment of SHL, dextran provided no more benefit than did dexamethasone or acyclovir. Earlier initiation of treatment improves the prognosis for patients with SHL.