Adams, an anesthesiologist and a vice admiral in the U.S. Public Health Service Commissioned Corps, is the nation’s 20th surgeon general, in office since September 2017. In the post, he oversees USPHS, chairs the National Prevention Council and has helped frame the nation’s opioid addiction crisis as a public health issue. (His younger brother struggled with substance abuse.)

Kids might not come with manuals, but Dr. Benjamin Spock’s 1946 “baby,” the parenting bible “Baby and Child Care,” came close to delivering one. The preachy pediatrician was on the front lines of child-rearing — and pacifism, as he counseled draft dodgers and bitterly opposed the Vietnam War — well into the Eighties and his 80s.

In matters of medicine, Mr. Spock, primo Vulcan-ologist and science officer aboard the starship USS Enterprise, deferred to chief medical officer “Bones,” Dr. Leonard McCoy, on the original hit series “Star Trek” (1966-69). Still, Spock was no slouch in the lifesaving department. When McCoy contracted the deadly xenopolycythemia and retired in 2369 to spend his final days on an asteroid ship, it was Spock who hacked out a cure, allowing McCoy to return to Starfleet service. Is it just a coincidence that actor Leonard Nimoy’s name echoes that of Leonard McCoy?

The fictional animal whisperer who shuns human patients in favor of beasts is possibly based on a real-life Scottish surgeon, Dr. John Hunter, who taught and collaborated with Edward Jenner, pioneer of the smallpox vaccine. According to the original 1920 book, “The Story of Doctor Dolittle, Being the History of His Peculiar Life at Home and Astonishing Adventures in Foreign Parts,” John Dolittle starts out as a respected M.D. living with his unmarried sister before learning to talk to the animals and allowing his home and life to be overrun by the menagerie. He eventually sets up a veterinary practice.

Not an M.D., but the reality-TV star of the Nat Geo Wild show is a real veterinarian and septuagenarian. A native of the Netherlands who practices in rural Michigan, Jan Pol is 76 and has said his favorite food is pork chops.

Writer, cartoonist and Oxford dropout Theodor Seuss Geisel used the pen name Dr. Seuss to publish over 60 books — and not strictly for children. He and his acclaimed work won oodles of awards including the 1984 Pulitzer Prize, Oscars, Emmys and Grammys. “Seuss” was his mother’s maiden name, as well as his middle name and original pen name at Dartmouth College, after he was banned from writing for its humor magazine under his real name because he was caught drinking by the dean in 1925. He toyed with other names before adopting “Dr. Theophrastus Seuss,” shortened to “Dr. Seuss” by 1928. He also wrote as Theo LeSieg — “LeSieg” is “Geisel” spelled backward.

Although he retired from medicine in 2013, Carson was a renowned neurosurgeon before entering politics and running for president in 2016. He became director of pediatric neurosurgery at Johns Hopkins Hospital at age 33 and earned fame for his groundbreaking work separating twins conjoined at the head. And now he’s head of the conjoined Department of Housing and Urban Development.

Psychologists and psychiatrists differ by degrees. Psychologists have doctorates but are not medical doctors like psychiatrists. As for Dr. Phil, Phil Calvin McGraw does hold a Ph.D. in psychology but is not a licensed psychologist.

The diminutive sex-therapy giant has a doctorate of education in family studies from Columbia University Teachers College. She previously worked for Planned Parenthood, where she was inspired to study under Dr. Helen Singer Kaplan at New York Hospital-Cornell University Medical Center. She is also a fellow of the New York Academy of Medicine. An author of 35 books and the syndicated column “Ask Dr. Ruth,” she takes a missionary’s position (ahem) on disseminating what she calls "sexual literacy."

Gupta is a neurosurgeon and the chief medical correspondent for CNN, where he hosts “Vital Signs.” He’s credited with breaking the news on Sen. John McCain’s glioblastoma diagnosis. Gupta fast-tracked his medical education with an eight-year medical program called Inteflex at the University of Michigan, securing a spot while still in high school. During the 2008 presidential campaign, he reported on the health effects of the presidency and charted the health of candidates in the documentaries “The First Patient” and “Fit to Lead.”

The 54-year-old rapper, record producer and entrepreneur, whose real name is Andre Romelle Young, announced in 2015 he had completed his doctorate (field unknown) and should now be addressed as “Dr. Dr. Dre.” And he seems to fixate on life-or-death issues. His label is called Death Row Records and he is the founder and CEO of Aftermath Entertainment. (At least he doesn't call his Beats audio gear "Dead Beats.")

Turkish American Mehmet Cengiz Öz is a medically trained cardiothoracic surgeon. But his detractors say he sold out to showmanship.

Dr. Alison Tendler is an ophthalmologist in Sioux Falls, S.D. She not only hawks the product but uses it.

Doc and mad scientist. And a lawyer. And a monster. The fictional character created by Scottish author Robert Louis Stevenson was introduced in the 1886 gothic novella “Strange Case of Dr. Jekyll and Mr. Hyde.” According to Bartleby, in the mid-1800s (about the time Jekyll would have been educated), medical students' few years of training centered on "natural philosophy," including such subjects as anatomy, physiology, chemistry, physics, mathematics, therapeutics, biology, surgery, sociology and philosophy.

Julius No is a fictional criminal scientist of Chinese and German descent played by Canadian actor Joseph Wiseman in the first James Bond film. Due to radiation exposure, the character has hands made of metal. If he had chosen to get a medical degree, he might have made a killing in robotic surgery.

Alfredo Darrington Bowman was a discredited diet guru and herbalist from Honduras who also practiced in New York City and Los Angeles. From humble roots, he grew wealthy, earning an estimated $3,000 a day before being arrested for money laundering in 2016, the year he died at age 82. Dr. Sebi classified food into six basic groups: live, raw, dead, hybrid, genetically modified and drugs. He prescribed a mostly vegan diet devoid of all groups except the “electric” live and raw foods, which he said tempered the acidic waste in the body. His celebrity clients included hip-hop singer Lisa Lopes of the R&B girl group TLC, actors Steven Seagal and John Travolta, comic-actor Eddie Murphy and pop royalty Michael Jackson.

The Doctor Who franchise refers to a rogue Time Lord from the planet Gallifrey nicknamed "the Doctor.” He (or she, in a modern-day twist) is centuries old and has the ability to regenerate and avert mortality, taking on a new appearance and personality. “Doctor Who” first appeared on BBC TV at 17:16:20 GMT on Saturday, Nov. 23, 1963 — 80 seconds later than its scheduled time, due to the extended news coverage of the assassination of President John F. Kennedy the previous day.

The brother of the marquee cereal tycoon was a medical doctor, nutritionist and health activist who ran a spa known as a “sanitarium” at the turn of the 20th century. No sugarcoating it: History — and the 1994 biopic “The Road to Wellville,” starring a buck-toothed Sir Anthony Hopkins as Kellogg — paint him as a flake.

Although “Jack the Ripper”— also known as “Leather Apron” and “the Whitechapel Butcher” — was never identified or apprehended, the culprit’s horrific crimes displayed an acute knowledge of anatomy: Victims were disemboweled or had their kidneys or uteruses removed. Jack’s daytime trade could well have been medicine.

Interestingly, the carbonated drink in the wine-colored can was formulated by Brooklyn-born pharmacist Charles Alderton. To test its appeal, he first offered it to the owner of Morrison's Old Corner Drug Store in Waco, Texas, Wade Morrison, who gave it a thumbs-up. Patrons at the soda fountain eventually began ordering it as the "Waco." Alderton gave the formula to Morrison, who named it Dr. Pepper. (The period after "Dr" was used intermittently in Dr Pepper logos until the 1950s, when it was discarded for stylistic and legibility reasons.) The recipe, still a trade secret, is alleged to be kept as two halves in safe-deposit boxes in two Dallas banks. A persistent rumor since the 1930s is that the drink contains prune juice, but the official Dr Pepper FAQ refutes this with "Dr Pepper is a unique blend of natural and artificial flavors; it does not contain prune juice." Theories about its name origins run amok. One notion: It was common at the time of the drink’s creation to include “Dr.” in the names of products to convey the impression they were healthful.

Rep. Kim Schrier has said she decided to run for her seat after a Republican health care bill was introduced last year that sought to scale back protections for people with preexisting conditions.