According to Garry Trudeau, Frank Sinatra did!
It’s not a “Medical Doctor Degree.” It’s “Doctor of Medicine” or “Medicinae Doctor.”
Herr Professor Dr. John Jacob Jingleheimer Schmidt takes too long to say.
I always insist on being called “Dr.” in all situations, including intimate moments with Mrs. J.
“Hel-Lo, Doc-tor!”
I can see how that might work.
No, it’s centuries older than that, as I mentioned in two previous posts:
When I see job openings for a professor they almost all say earned doctorate is a requirement. Because an honorary degree is a real degree, it’s just not awarded the same way as a regular PhD.
Trivia via How-2 Geek: “Did You Know? The original version of the Hippocratic Oath calls for doctors to teach the children of their teachers the art of medicine without reward or agreement (free of charge).” But why didn’t the teachers teach their own children? Is it the who-shaves-the-barber quandary?
I always introduce myself to patients as First Lastname and let them decide how they want to address me. When I call, like I have a lot for these telemedicine days, I usually introduce myself as Dr. Lastname from Mymedicalcenter to avoid any confusion. My wife on the other hand introduces herself as Dr. Herlastname because their is still a large majority of patients who will call her nurse despite the white coat with her name, MD embroidered on it. Hell they still call her nurse even after she says she’s Dr. Herlastname so seems like its a good idea to reinforce as much as possible that women are doctors too.
Having said that outside the hospital I am Firstname Lastname unless it’s a very formal situation where everyone is going by titles.
Regarding how people seem to take on someone’s desire to use their title at all times, I admit to a sick compulsion to watch Gordon Ramsay’s Kitchen Nightmares where he goes to failing restaurants and attempts to fix them with a heady mix of sensible business advice and profuse swearing.
In the US version he is invariably addressed by everyone in the kitchen as ‘Chef Ramsay’, while in the UK version its usually ‘Gordon’, or occasionally ‘you bell-end’.
Its an interesting inversion of how status is recognised in Britain’s class-ridden society and the more self-consciously egalitarian US.
I once had a guy introduce himself to me at a Mensa meeting as “Doctor John Doe” so I replied that I was “Bachelor Richard Roe” (names changed to protect the innocent). In what was a purely social setting I thought his use of his title was a bit pretentious.
Entymology.com does not seem to agree with you. The word was not used to specifically denote a medical practitioner but as a term for a holder of a doctorate in a discipline. Including but not exclusive to medicine.
Using the word legally as opposed to colloquially to specifically to denote a medical practitioner seems to date to 1838 in the UK, through Royal College of Medicines decision to “regard in the same light, and address by the same appellation, all who have obtained its diploma, whether they have graduated elsewhere or not.” In the US, from 1846 I believe.
In part this was because the US did not have the distinction between physicians, barbers and apothecaries that the UK did.
I shan’t vouch for the veracity of it, but I have been told that in the UK surgeons often don’t refer to themselves as doctors still.
It would be peculiar if the word had been medicine specific as early as the 1600s as that would mean that the practice of phDs in other disciplines had re-evolved at some point.
“Dammit, Jim, I’m a Doctor, not a physician!”
As a historian I tell my successful PhD students they can make everyone call them doctor for a week, then knock it off. I also tell them if people ask if they are medical doctors, they can say, “No, but I can take your history.”
Miss Manners cites her uncle, the labour historian Selig Perlman, on insisting on being called doctor in academia: “A PhD is like a nose — everyone has one. It’s only conspicuous if you don’t have one.” She adds, and this may be of interest to those concerned about pronouns, that etiquette requires one “Address people as they wish to be addressed.”
PhD here. I never use the title outside of work. People might ask me to deliver a baby on an airplane or something. Ick.
In the UK or Australia, if he practiced as a maxillofacial surgeon he would insist on being called “Mr.” rather than “Dr.”
You’ll have to help me out here, as to why you think this passage doesn’t indicate a usage of “doctor” to mean practitioner of medicine as early as 1400, generally being accepted by the end of the 16th century, and certainly not derived from American usage, as you’ve suggested. I’m not saying that it was the exclusive meaning; I’m saying that since 1400 onwards, it has had two related meanings: the highest degree in an academic discipline, and a medical practitioner. The latter sense is not original to American usage.
How does that not support my earlier posts, that the term “doctor” to mean a medical practitioner, dates to 1400 in England? 
The Etymology Online summary is supported by the entry for “doctor” in Dr. Johnson’s Dictionary of the English Language, first edition 1755:
In support of meaning # 3, Johnson cites works by Shakespeare, Dryden and Swift.
Macbeth and Cymbeline are both dated to the early 17th century, which is consistent with the dating in the Etymology Online entry.
Overall, Johnson’s Dictionary, and the works he cites in support of his definition of “doctor” as a medico, are not consistent with the suggestion that this meaning of “doctor” was derived from American usage in the 19th century, which is what I understood you to be saying?
Possibly because the father would be dead by the time the children would be old enough to be trained as doctors? Life expectancy may not have been that good.
Bumped.
In the German language, Doctor is the correct honorific for all those who have earned the title by having successfully completed their university education with a doctoral thesis and defence. For the medical profession, the examination required to practice is the “Staatsexamen”, a doctorate is not needed for approbation, but is granted for a half-a-year research project and written thesis (as opposed to 4-5 years for a PhD in the sciences). If you call for a medical professional, you call for an Arzt, although “Doctor” is used as honorific in a formal interchange.
In the 35 years since I got my PhD (Biochemistry), there were just three occasions in which I spontaneously brought up the subject:
1- In a company I worked for, some higher-ups gave some visitors a guided tour through the labs. They introduced my male colleagues as Dr. This and Dr. That, me as Mrs. Anaglyph. I reminded them that I worked just as hard for my PhD as my male colleagues. Just because I am female does not mean that I am the lab technician.
2- In a self-improvement group settings, my fellow participants and I all introduced ourselves by our first names. The leader/moderater then introduced himself as Dr. Lastname. I piped up to say "In this case, you may call me Dr. MyLastName. Of course, the German language makes much more of a difference between formal address (last name, different pronoun) and the familiar address (first name) than English, and to insist on an asymmetry in address between adults of similar social status is considered quite rude. As a lecturer, I would address young students as Mr. or Ms. Lastname. Once they joined the research group and became “family”, they would be invited to switch to familiar address, using first names in both directions of the conversation
Yes, as explained in the thread, it is mainly confusing in English, if at all, since the title “doctor” has nothing to do with medicine specifically; for instance if I were wounded my first impulse would not be to run to a doctor ecclesiae universalis. 
As for your second point, if someone does insist on being a sexist asshole and/or rudely starts addressing you like they’re your buddy (rare, but for sure it happens) then I agree it’s time for, “That’s Frau Professor Doctor Doctor Anaglyph to you.”
I’ve got my Ph.D., but the only time I use the title is when I tick off the “title” thing on professional magazine address labels, or when we’re applying for a grant, or something.
The only time anyone ever addresses me aloud as “Doctor” is When They Want Something.