Background: Sildenafil citrate has been reported to induce temporary sensorineural hearing loss,tinnitus and dizziness.
Objective: To evaluate the effects of sildenafil citrate on the guinea pigs cochlear structure and function using Otoacoustic
Emissions (OAEs) and light microscopic H & E cochlear sections.
Patients and Methods: This experimental study was conducted on 45 healthy adult male pigmented guinea pigs in
Otolaryngology-Head and neck Surgery and Histology Departments in Suez Canal University, Ismailia-Egypt. Animals
were randomly divided into three groups: Group 1 (n=15): control group. Group 2 (n=15): received the therapeutic dose
of sildenafil citrate. Group 3 (n=15): received double the therapeutic dose of sildenafil citrate.
Results: DPOAEs recorded from the three groups showed that the lowest amplitude was at 1006 kHz (10.4dB) and the
highest at 6060 & 8084 kHz (43.9 & 42.1dB) respectively without statistically significant intergroup difference. In the
H & E cochlear sections, there was disorganization and vacuolation of almost all cells of organ of Corti in group 2 and 3
compared to group 1. Lightly stained cytoplasm, karryorrhectic nuclei and pyknotic ones were also seen. These changes
were more marked in group 3 which showed also some cellular loss in some sections.
Conclusion: Therapeutic dose of sildenafil citrate affects the cellular structure of organ of corti without detectable effects
in DPOAEs.