Doctors are not the only ones with bad manners, irritating personalities and ridiculous agendas. Out there in waiting rooms everywhere sit the counterparts of the difficult doctor: the impossible patients whose names on the schedule make the doctor cringe.
Some are just bad matches for their own particular doctor. Some behave in ways that would upset any doctor anywhere. A few may be acting out on purpose.
But whichever they are, the experts say it does not always have to be that way.
"When people think they're sick, they can be really difficult," said Dr. William D. Clark, president of the American Academy on Physician and Patient, an organization devoted to streamlining doctor-patient communication. "But I'm totally on the patient's side in all of this."
When doctors learn the right skills, Dr. Clark said, it is rare that a difficult patient does not become considerably easier.
No doctor likes every patient who walks through the door. Yet, while psychiatrists have long been trained to note their own negative reactions to patients and use the information in therapy, other doctors were, until recently, advised to bury their feelings and move on. To do otherwise was considered unprofessional.
In the last decade, though, educators have begun to suggest the opposite. They remind doctors that it is normal to find some patients hard to care for (or even to be in the same room with). By noticing when patients ring their bells, and trying to figure out why, doctors can learn to accept and even change patients' behavior by changing their own.
What makes for a problem patient? Sometimes a characteristic resonates with a doctor's background, like a timbre of voice that replicates the pitch of the doctor's mother's incessant faultfinding.
Sometimes, the problem is behavior that few doctors can tolerate without practice. Dr. James E. Groves, a Harvard psychiatrist, identified some patterns in a 1978 article in The New England Journal of Medicine called "Taking Care of the Hateful Patient."
Some patients are "dependent clingers," Dr. Groves wrote. They unconsciously try to turn the doctor into a parent, bringing to the office insatiable needs for affection and attention, then becoming sulky and hostile when the needs are not met.
Some are "entitled demanders," who react with fury to setbacks and routinely threaten to sue. Some are "manipulative help-rejecters," hypochondriacs who are never helped by what a doctor does or says.
Finally, there are the patients who seem determined to destroy themselves: the smokers who keep smoking even after they develop lung cancer, the drinkers with liver failure. Doctors often find themselves wishing these patients would "just die and get it over with," Dr. Groves said.
Dr. Clark said a few basic tools could often help. First, doctors need to cultivate the self-awareness to know when they are reacting not to a specific patient but to unrelated incidents in their own past.
They must learn to express empathy in words as well as gestures. They must set limits and make compromises. They must learn not to yell back at an angry patient, but to acknowledge quietly that in the patient's position they might well be angry too.
But every once in a while, patients will confound all attempts to soothe them, because they are being difficult on purpose.
That was the tactic chosen by Stephen H. Schneider, a professor of biological science at Stanford, when he developed an unusual form of lymphoma in 2001.
During his previous encounters with the health care system for more routine ailments, Dr. Schneider said, he behaved like an ordinary patient, doing what he was told without making a fuss.
But when faced with a rare, life-threatening disease whose optimal treatment was far from clear, he immediately and consciously morphed into "The Patient From Hell," which is the title of the book he published this fall describing his experience.
"I was a real pain," Dr. Schneider said.
He spent countless hours online investigating his illness. He asked endless questions about recommended treatments. He name-dropped his way to one second opinion after another. He lobbied his doctor for tests and medications, and even asked the hospital to buy specific machines for his care.
It all worked out well. Now, four years into a remission of his cancer, Dr. Schneider and his doctor are still friends, and he has answered hundreds of e-mail messages from patients who have read his book.
His advice to all: be as educated and ask as many questions as you can - or find someone to do it for you; becoming a patient from hell could save your life.