I had tinnitus occasionally before treatment but while on ethambutol it became more frequent and bothersome. After treatment the tinnitus improved monthly as the time went on, I rarely get it anymore. As far as hearing loss, I did have some loss but I didn’t get tested until 8 months into treatment so I can’t say it was meds. My last one after treatment slightly improved, my hearing loss isn’t enough to warrant hearing aids. I learned about getting baseline hearing test here but it took me 8 months to get appt.