NAC may have a role in the prevention or early treatment of hearing loss, although research is still in the early stages.
Hearing loss is complex and can occur for many reasons, but increased levels of oxidative stress within the ear is an important contributing factor. Excessive levels of reactive oxygen species|ROS within the ear canal can damage or kill auditory hair cells — the cells responsible for converting sound vibrations into electrical signals that the brain can understand — leading to hearing loss.[1]
Research suggests that NAC may reduce the risk of drug-induced hearing loss when used concurrently with potentially ototoxic drugs (i.e., drugs that are toxic to the ear, such as aminoglycoside antibiotics or cisplatin).[2][3] NAC may also have a protective effect against noise-induced shifts in hearing thresholds (i.e., exposure to noises so loud that they temporarily or permanently raise the minimum volume at which a sound can be detected), specifically for higher sound frequencies (4–6 kHz).[1] For sudden hearing loss (an unexplainable, rapid loss of hearing), combining NAC with corticosteroids may be more effective for regaining hearing than corticosteroids alone.[4]