As Dr. Danielle McCarthy listens to a man beg for a prescription for painkillers, she weighs her possible responses.

A 31-year-old emergency room physician, she listens patiently as the man tells her that “every morning I wake up in pain,” describing the agony he continues to endure, three years after being injured in a car wreck.

He has tried physical therapy, acupuncture and chiropractic treatment, he says. Nothing works except pills, he insists, as his voice grows louder and more demanding.

Their exchange is similar to conversations that take place on almost every shift at Northwestern Memorial Hospital here, Dr. McCarthy said. But it is fiction — part of an interactive video game designed to train doctors to identify deceptive behavior by people likely to abuse prescription painkillers. The patient is an actor whose statements and responses are generated by the program.

The video game was designed based on research by Dr. Michael F. Fleming at the Northwestern University Feinberg School of Medicine and draws on technology used by the F.B.I. to train agents in interrogation tactics. It teaches doctors to look for warning signs of drug abuse, like a history of family problems, and to observe nonverbal signs of nervousness, like breaking eye contact, fidgeting and finger-tapping.

The game, which is in its final phase of testing, is aimed at primary care and family doctors, who often feel uncomfortable and unqualified assessing their patients in this regard.

“This isn’t something medical students have traditionally been trained for,” Dr. Fleming said. “These are hard conversations to have.”

It can be a thorny matter, Dr. McCarthy said, because physicians are trained to help patients, but they do not want to enable drug abuse. “You don’t want people to be in pain,” she said. “And you’re put on the spot. I’ve had patients yell at me. I’ve never been hit, but once or twice I’ve felt physically threatened.”

In 2017, for the first time, the number of deaths from drug overdoses surpassed those from highway traffic accidents, according to Gail Hayes, a spokeswoman for the Centers for Disease Control and Prevention. She said misuse of prescription medication has been largely the cause. About 75 percent of overdoses involved prescription drugs, she added.

So health care professionals are searching for better ways to distinguish patients who can be trusted to use prescription pain medications properly from those out to abuse them. According to the C.D.C., prescription drug abuse is the fastest growing drug problem in the United States, fueled by the use of highly addictive opioid analgesics like OxyContin.

The Web-based interactive video game, which will soon be available online for a fee to medical schools and health care providers, includes about 2,000 statements by the patient, ranging in tone from charming to irate. A doctor can choose from 1,500 questions and responses, selecting one from five to seven options that appear on the screen when it is time to speak to the patient.

The dialogue is drawn from research by Dr. Fleming, based on interviews with more than 1,000 patients who were receiving opioids for pain. “We have 95 percent of what a patient and doctor would say or do,” he said.

Sharp skills are needed to assess a patient’s motives, he said, because an objective measurement, like from a blood test or an X-ray, is not available to gauge pain, and the opioids can be highly addictive.

The game’s software was developed by Dale E. Olsen, a former professor of engineering at Johns Hopkins University. He is the founder and president of Simmersion, a company that has created simulation training programs for the F.B.I. The game’s development was financed by a $1 million grant from the Small Business Administration and the National Institute on Drug Abuse. Dr. Olsen, who has a Ph.D. in statistics, said the game would cost users about $50 an hour. It is designed to be used for 10 sessions of 15 to 20 minutes each. He said customers would most likely include medical schools, as well as private and government health care providers.

The game encourages doctors to adopt a more collaborative and less accusatory approach with patients, Dr. Olsen said. “The goal is to build rapport,” he said.

Dr. McCarthy, wearing headphones and blue scrubs, faces the computer screen, where the patient, named Tom, a trim man with a neatly cropped beard, is asking for pain medication.

The physician asks Tom to describe his pain. Tom points vaguely to his lower back. She asks about whether he has ever had any problems with pills. He acknowledges that he once accidentally took too many pills, but that it was “no big deal.”

When she asks him to submit to a drug screening, he is testy, but agrees to do so if she insists — “and then I want my pills.”

At the end of the interactive portion, the game awarded Dr. McCarthy high marks for communication skills, for asking for a drug test and for declining the request for a prescription. She lost points for not asking enough questions.

Dr. McCarthy nodded at the screen in acknowledgment of her score. She explained that there are time constraints in her work.

“We move pretty quickly in the emergency room,” she said. “We’re not usually going to have time for 60 questions.”

She sometimes has had a hunch that a patient was exaggerating or fabricating pain, she said. She found the training useful, she said, because it offered new suggestions of responses to patients.