Q. Why are hearing aids so incredibly costly? Is it patents? A lock on manufacturing? With today’s digital revolution, it would seem that they should be approaching the cost of eyeglasses.

A. Hearing aids remain expensive — $900 to $3,500 or more per ear — but that is likely to be changing soon. The Food and Drug Administration Reauthorization Act of 2017, which became law in August, includes a provision for selling hearing aids over the counter to adults with mild to moderate hearing loss in two to three years. The extra time allows the F.D.A. to establish safety, effectiveness and labeling standards. Under the new law, hearing aids are expected to cost around $300 or less per ear.

Experts don’t know exactly why hearing aids are still so costly, except that companies continue to invest in improvements, and fees usually cover the services of a highly trained audiologist.

Cost reductions can’t come soon enough for those who depend on hearing aids. Barbara Kelley, executive director of the Hearing Loss Association of America, said her office gets a handful of calls every day from people needing help paying for hearing aids. The association refers them to the Department of Veterans Affairs, Medicaid or foundations like the Lions Club, depending on their military status and where they live. “It’s still really tough,” she said. Medicare does not cover the cost of hearing aids, though there’s a bill before Congress that would require such coverage.