Possessing a genius intellect and an eidetic memory, Howser participates in a longitudinal study of child prodigies until his 18th birthday. He earned a perfect score on the SAT at the age of six, completed high school in nine weeks at the age of nine, graduated from Princeton University in 1983 at age 10, and finished medical school four years later. At age 14, Howser was the youngest licensed doctor in the country. As a newspaper article stated, he "can't buy beer but can prescribe drugs".
The series begins on Howser's 16th birthday; the cold open of the pilot episode shows him stopping his field test for his driver's license to help an injured person at the scene of a traffic accident. Howser is a resident surgeon at Eastman Medical Center in Los Angeles, and still lives at home with his parents. His best friend and neighbor, Vinnie Delpino (Max Casella), is a more typical teenager—climbing through Howser's bedroom window to visit—and connects him to life outside medicine. Howser has kept a diary on his computer since 1979; the episodes typically end with him making an entry in it.
Howser seeks acceptance by both others his age and his professional colleagues. Many episodes also deal with wider social problems: AIDS awareness, racism, homophobia, sexism, gang violence, access to quality medical care, and losing one's virginity are topics, along with aging, body issues, and friendship.
Howser initially has a girlfriend, Wanda Plenn (Lisa Dean Ryan), but they break up after she leaves for college; he also begins a trauma surgeryfellowship and moves into his own apartment. Bochco intended to end the show with a "season-long story arc for Doogie where he becomes disaffected with the practice of medicine and quits medicine to become a writer". ABC abruptly canceled the show due to low ratings, preventing Bochco and the show's writers from implementing the storyline other than Howser's resignation from Eastman and departure for Europe in the final episode.
Doogie Howser, M.D. won the Academy of Television Arts and Sciences' Emmy Award three years in a row for Best Sound.
The weekly, half-hour dramedy was created by Steven Bochco. He originated the concept and asked David E. Kelley to help write the pilot, giving Kelley a "created by" credit. Harris was the first actor the show's staff found that could convincingly play a teenaged doctor, but ABC opposed his casting. Bochco's contract required that the network pay an "enormous" penalty if it canceled the project, so ABC was forced to let him film the pilot. The network still opposed Harris's casting and disliked the pilot, but after successful test screenings ABC greenlit the show. The soundtrack of the series is by Mike Post and uses Post's trademark mid-to-late 1980s Yamaha DX7 synthesizer.
From left to right, Lawrence Pressman as Dr. Canfield, Neil Patrick Harris as Doogie Howser, Mitchell Anderson as Dr. McGuire and Kathryn Layng as Nurse Spaulding
Max Casella as Vincent "Vinnie" Salvatore Delpino, Howser's best friend since they were five years old. Delpino resists his father's demands to join the family business and attends film school instead.
Lisa Dean Ryan (seasons 1–2, recurring in season 3) as Wanda Plenn, Delpino's high-school classmate and Howser's girlfriend. After her mother dies in an automobile accident Plenn's relationship with Howser suffers, and after she leaves for the School of the Art Institute of Chicago they end their relationship.
Lucy Boryer (seasons 1–3, two episodes in season 4) as Janine Stewart, Delpino's girlfriend and Plenn's best friend. She drops out of college and becomes a buyer for a department store.
Lawrence Pressman as Dr. Benjamin Canfield, head of Eastman Medical. Canfield is an old friend and classmate of David Howser, and persuades him to join the hospital to run its family practice.
Mitchell Anderson (seasons 1–2) as Dr. Jack McGuire, a resident at Eastman and Howser's friendly rival. A visit to rural Mexico inspires him to leave the hospital to serve the poor overseas.
Kathryn Layng as Mary Margaret "Curly" Spaulding, a nurse at Eastman. Spaulding occasionally dates McGuire and, briefly, both Canfield and Howser.
Markus Redmond (seasons 2–4) as Raymond Alexander, an orderly (and later an EMT) at Eastman. Alexander meets Howser after taking him hostage during a convenience-store robbery; after finishing his sentence, Howser helps him get a job at the hospital.
Rif Hutton as Dr. Ron Welch, a fellow doctor who is also friends with Howser.
Robyn Lively as Michele Faber (seasons 2 and 4), a nursing student. She becomes Howser's girlfriend shortly before he decides to leave Eastman and go to Europe.
Barry Livingston as Dr. Bob Rickett (seasons 2–4), a fellow doctor working at Eastman.
Anchor Bay Entertainment released all 4 seasons of Doogie Howser, M.D. on DVD in Region 1 between 2005–2006. These releases have since been discontinued and are out of print. Before the DVDs were discontinued, there were plans for a Complete Collection release which was announced on August 28, 2008, which was eventually canceled .
In the United States, Doogie Howser, M.D. had a run in local syndication between September 1993 and September 1996. The show also aired on cable on Odyssey Network (now Hallmark Channel) from 1999 to 2001. The show had not aired anywhere else until The Hub began airing reruns on October 11, 2010.
Harris has satirized his years playing a teenage medical doctor several times.
In an episode of Roseanne, Roseanne has a dream after having undergone breast reduction surgery. She goes to the mirror and realizes that she has comically larger breasts than before. Doogie Howser (Harris) comes in and asks an upset Roseanne if they were supposed to be bigger than they are in the dream. Roseanne screams but then is woken up by her husband Dan. To make sure she was dreaming, she looks under her bedsheet, sees the surgery went as planned, and sighs, "Way to go, Doogie!"
In the 2004 comedy Harold & Kumar Go to White Castle, Harris—playing a fictionalized version of himself—claims to have "humped every piece of ass ever on that show" (except the hot nurse, over whom he expresses regret). Harris is referred to as "Doogie Howser" while stealing Harold's car from the convenience store. In Harold & Kumar Escape from Guantanamo Bay, Harris remarks, after taking psychotropic mushrooms, "Dude, I was able to perform an appendectomy at 14, I think I can handle a few 'shrooms".
In 2008, Harris appeared in commercials for Old Spice deodorant, claiming to be an expert because he "used to be a doctor for pretends".
During the opening of the 2009 TV Land Awards, Harris, the host, travels through "The TV Land Zone" (a spoof of The Twilight Zone), where he finds himself the star of TV classics. At one point, Harris walks into a doctor's office, dressed as Doogie, while the Doogie Howser, M.D. theme plays. After realizing where he is, he storms out, saying, "No no no, not gonna happen! Check my contract!"
On the January 10, 2009 episode of Saturday Night Live, the "SNL Digital Short" featured guest host Harris leading a full orchestra version of the Doogie Howser theme. When the song concludes, he turns toward the camera and sheds a tear.
On the March 14, 2011 episode of Jimmy Kimmel Live!, a "real doctor" played by Harris endorses Kimmel's Jim-Miracle Diet, as the Doogie Howser theme plays.