A subway rider, obviously not too familiar with local geography, got aboard an Orange Line train yesterday at Foggy Bottom. She looked for directions on a map displayed at one end of the car and became bug-eyed: instead of stations with such names as Metro Center, Union Station and Capitol South, they had such names as Diabetes, Pain and Headache.

A friendly local suggested she turn around and look at a map on the other side of the car.

But what was the first map all about?

It was a clever, if disconcerting, poster advertising the Health Care Expo now going on at the Washington Convention Center. The centerpiece of the poster is a mock map of the Metro system, with names of illnesses, problems and medical techniques substituted for the actual names of stations on the various lines.

No station names are shown in downtown Washington. But Arlington Cemetery shows up on the map as High Blood Pressure, the Pentagon as Sports Medicine, National Airport as Arthritis, Woodley Park/Zoo as Aging, Van Ness as (appropriately, considering the proximity of the UDC campus) Computers, an undefinable station farther out on the Red Line as Drug Abuse, Fort Totten as Anorexia/Bulemia, Takoma Park as Headache, Silver Spring as Mental Health and a station on the Green Line beyond Anacostia as Alcohol Abuse.

When I finish this column, I'm going down to the station to take a train home to Stress.