Sudden Sensorineural Hearing Loss Due to Drug Abuse

In the last 10 years, there has been an emergence of reports related to opioid-induced sudden sensorineural hearing loss (SSNHL). The underlying pathology is not completely understood, and the mechanism(s) of action of these drugs in the inner ear remains to be determined. Reports of SSNHL due to the abuse of opioid peptides and other drugs suggest that the opioid system in the inner ear is affected. The reversible or irreversible effect on auditory function depends on the type of drug used and several other factors, including duration and time of exposure as well as the health status of drug users. Abuse of hydrocodone + acetaminophen (Vicodin hydrocodone/paracetamol; Abbott Laboratories, Worcester, MA) has induced permanent hearing loss in several individuals. In contrast, abuse of heroin-induced hearing loss that was sometimes reversible. The widespread expression and physiological action of endogenous peptide opioids and their receptors in the inner ear suggests that pharmacological treatment for druginduced hearing loss is possible. The present study reviews the basic concepts of opioids and their receptors, provides clinical examples of hearing loss mediated by opioids and related drugs, reviews experimental evidence of the presence of opioids and their receptors in the inner ear (animal models and human studies), and describes the cellular targets affected by opioids and other recreational drugs.