At my house, classic TV is a given. My 93-year-old father-in-law enjoys watching reruns of westerns, Perry Mason, Andy Griffith and Gomer Pyle. With these old favorites come commercials targeting an aging population: Medicare Advantage plans, reverse mortgages, and miracle solutions for neuropathy, with free consultations for the first 250 people who call.

Every time we see one of these neuropathy advertisements, my father-in-law looks at me hopefully. 

His neuropathic foot pain has been intractable for decades. All the usual medical solutions have either brought minimal relief or intolera...