What causes ringing in the ears?

Tinnitus is the perception of sound with no external source, most commonly a ringing, hissing, buzzing, or roaring. The dominant cause is damage to the hair cells of the cochlea, which convert sound vibration into nerve signals. When those cells are damaged, typically by loud noise exposure but also by aging, certain medications, and some medical conditions, the auditory pathway loses input at particular frequencies, and current understanding is that the brain compensates by increasing gain in those pathways, generating perceived sound where none exists. That model explains why tinnitus is often loudest in quiet environments and why it frequently accompanies measurable hearing loss even when the person had not noticed the loss.

Common contributors are worth listing because several are avoidable or reversible. Cumulative noise exposure from concerts, power tools, firearms, and headphones is the leading one. Earwax impaction is a simple and fixable cause. Numerous medications are ototoxic, including high-dose aspirin, some antibiotics, loop diuretics, and certain chemotherapy agents. Head and neck injuries, jaw joint problems, blood pressure and vascular conditions, and Meniere's disease also produce it. Tinnitus that pulses in time with your heartbeat is a distinct category called pulsatile tinnitus and should be evaluated promptly, since it can indicate a vascular abnormality.

There is no cure for the common form, and any product marketed as one deserves skepticism. What helps is management: sound therapy using background noise or maskers, hearing aids where hearing loss is present, which often reduce tinnitus by restoring input, and cognitive behavioral therapy, which has the strongest evidence base and works by reducing distress and attention rather than the sound itself. Prevention is the part with the most leverage: hearing damage is cumulative and permanent, so protecting your ears at concerts, while using tools, and by keeping headphone volume moderate is the intervention that actually matters. See a doctor for tinnitus in one ear only, sudden onset, or tinnitus with hearing loss or dizziness.