Idiopathic sudden sensorineural hearing loss (ISSHL), a common otologic emergency, presents mostly as an abrupt onset unilateral hearing loss, aural fullness, often with vertigo and tinnitus, usually upon awakening in the morning. Its etiopathogenesis is multifactorial, so a number of different therapeutic regimens are in practice, hyperbaric oxygen (HBO2) therapy being an effective yet underutilized one. Not all cases recover completely even after treatment. Here we describe two cases of ISSHL, diagnosed on the basis of clinical examination and pure-tone audiometry, who had a complete recovery following administration of HBO2 therapy in addition to medical treatment. These cases are reported to highlight the effectiveness of this modality in a physician's armamentarium.