Not every hearing loss claim is about noise. A long list of medications can damage the inner ear - a property called ototoxicity - and when the medication was prescribed to treat a service-connected condition, the resulting hearing loss can be service connected in its own right.
This is a secondary claim, and it follows the rules in 38 CFR 3.310.
The medications involved
The ototoxic list is long, and several of its members are common in veteran care: high-dose loop diuretics used in heart and kidney conditions, certain chemotherapy agents, high-dose or prolonged salicylate and NSAID use, some antibiotics given intravenously, and long-term high-dose aspirin therapy. The damage can be temporary or permanent, and it can hit hearing, balance, or both.
The practical point is the chain: service-connected condition, prescribed treatment, documented hearing change. Each link is a record somewhere in the file.
How the secondary claim works
Under 38 CFR 3.310, a disability caused or aggravated by an already service-connected disability is service connected in its own right. For ototoxic hearing loss, the opinion has to connect three things: the service-connected primary condition, the medication actually prescribed for it, and the hearing loss, with reasoning that the medication was a contributing cause.
The claim is strongest when the timeline is clean - normal or better hearing before the medication, documented change during or after it, and no competing explanation that fits better. Our secondary service connection guide explains the standard the VA applies.
What the evidence has to show
Three records carry this claim. The prescription record showing the medication and dose. The audiological record showing the hearing change - which is why periodic audiograms matter if you take a known ototoxic drug long-term. And the medical opinion tying it together with mechanism, not assertion.
When the medication came from VA care, the prescription history is easy to obtain. When it came from private care, pharmacy records fill the gap. Our evidence guide covers the file as a whole.
Where an independent medical opinion fits
The VA often concedes the hearing loss is real and the medication happened, then denies the link between them. That is the medical question, and it is what a reasoned opinion answers: it reviews the records, explains the ototoxic mechanism and dose relationship, addresses the age and noise alternatives, and reaches a conclusion. Our nexus letter guide explains what that contains, and a medical records review is where veterans start when they are not sure the file supports one.