SSRIs and the PDR; doctor's smarts and training

I recently came across someone who claimed that a full medical education is not needed to proficiently pick an SSRI drug... it's sufficient to read the PDR, the person said. I challenged that person to produce some pharmacokinetics and pharmacodynamics considerations involved in the question of modulation of serotonin receptors, actions of these drugs in various systems, and drug-drug interactions. The person did not do that, but kept doubling down, and insisting that he/she could figure it out better than doctors, despite this person possessing no medical education.

I grew frustrated and walked away from the discussion, but here, for anybody who might be interested and for the record, I'll add a little list of why the issue is far more complex than what can be ascertained by merely reading the PDR.

Sure, that's my narcissism speaking... I'm tagging a witness of the above discussion (none of the people I'm tagging was the person in question) because by walking away from the discussion, this could be interpreted as proof that I couldn't substantiate my claim about the complexity of the issue... which is far from the truth. I can perfectly substantiate it, and will be doing it now. Whoever is not interested in this (likely 99.9% of the people here) can skip the next several paragraphs (in between the markers -------- ) and go to the last part of this post, which introduces some other points that may be more interesting to discuss at large.

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So, serotonin receptors come in several subtypes. The 5-HT receptors 1, 2, 4, 5, 6, and 7 are metabotropic (G-protein-coupled). #3, though, is ionotropic (ion channels). There are also sub-receptors (5-HT 1a through 1f; 2a, 2b, and 2c; 3a and 3b; for the 4-type receptor the number of subtypes is still disputed; 5a and 5b; the 6-type has no subtypes; the 7-type has a subtype called T7.

1 and 5 are inhibitory. 2, 3, 4, 6, and 7 are excitatory. Different drugs have different actions in these receptors; it is important to know to what degree different drugs act on each one, to fully understand the drug's profile.

These receptors have genetic polymorphism, which is also the case for serotonin transport pump genes with promoter sequences. Epigenetic modifications are possible with methylation and acetylation to decrease or increase the production of a specific gene product - this is a fertile camp for future smart pharmacology research and development, and genetic therapeutics (an area still in its infancy). Anyway, even though we're not there yet, this genetic polymorphism affects how a patient reacts to a drug (more on this, later).

Another issue is the geography of the serotonin system: not only they exist in the brain but also in the gastrointestinal system and platelets (which has several clinical implications for side effects; that is, it is important to, again, understand the geography of receptor location and the potential for each drug to act - in undesirable ways - on other receptor-rich areas that are not in the brain).

Other issues to be considered (more in research settings than clinical ones) are presynaptic and postsynaptic receptors, the variability of subreceptor densities in the same neuron, serotonin neurons' postsynaptic targets, and the role of interneurons to change the outcome of the signal.

Also worthy of attention are the various pharmacological activities drugs can have on a serotonin receptor: agonist, partial agonist, antagonist, inverse agonist, and allosteric modulator. While all SSRIs will be similar in this regard, other drugs the patient may be taking might influence the intended action and expected efficacy, if they have one of the above activities.

What about the P450 system? SSRIs inhibit CYP2D6, the most potent inhibitors being fluoxetine, norfluoxetine, and paroxetine. Norfluoxetine inhibits CYP3A4, but the others, not significantly. Fluvoxamine is a potent inhibitor of CYP1A2, but the same is not true of citalopram, fluoxetine, paroxetine, or sertraline.

Because of its potent CYP1A2 inhibition, fluvoxamine has a significant impact on the metabolism of caffeine, clozapine, olanzapine, theophylline, propranolol and tacrine, to mention a few examples.

Fluvoxamine and fluoxetine are also potent inhibitors of CYP2C19; this is very important to the metabolism of all of the tricyclic antidepressants, several neuroleptics, opiates, betablockers, and antiarrhythmics.

These are some examples... but each of the others will have their own inhibition profile, which will be very important in considering what other drugs a patient is taking, when picking one of the SSRIs.

Finally, it is also important to understand the issues introduced by the other way around, that is, whether or not other drugs impact on SSRIs via the P450 system. For example, N-desmethylcitalopram, fluvoxamine, fluoxetine and paroxetine are metabolized through CYP2D6, but not sertraline.

In selecting an SSRI, it is becoming increasingly useful to order a genomic analysis, to verify the patient's genetic make-up regarding the P450 system. Mutations affecting these enzymes will make of some subjects, fast or slow metabolizers of specific SSRIs, which will have an enormous impact on efficacy, dosage, and side effects/toxicity. Genomic analysis will hopefully, in the near future, also provide an understanding of the polymorphism I was talking about, earlier on. The cost of these tests (some $2,500) and the fact that they are still incomplete in the number of genes they look at, is still limiting their ability to be ready for prime time, but this field is progressing fast.

Anyway, this is just to show how complex the issue is, and how a lay person reading the PDR is not equipped to sufficiently understand what is at stake. QED.

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Now, here is where it makes a bit of sense to open up this discussion, if by any chance someone is reading this poorly frequented part of the forum and wants to chime in: the issue of medical provider education.

So, in the United States PAs and nurse practitioners, unlike in many other countries, are allowed to prescribe these drugs. Their training, though, is just a tiny fraction of the training required of medical doctors (and the latter get tested on the results of such training by the USMLE - United States Medical Licensing Examination - steps 1, 2, and 3, unlike PAs and licensed nurse practitioners). The cursory learning of areas such as genetics, pharmacology (dynamics, kinetics), immunology, etc. (so many other areas in the basic medical sciences) as applied to Medicine, that is provide to PA students, appears to me to be insufficient to provide a full understanding of the stakes.

I read a piece by a former PA who subsequently (after several years of PA practice) went to medical school. She wrote that it was only when she was able to go through a full-blown medical education, that she understood the VAST difference in fund of knowledge between PAs and MDs.

So, under the risk of appearing elitist, is it entirely safe for the American public to have here this system of PAs and LPNs, unlike many other developed countries? I regularly teach medical students and PA students... and while the former are often equipped to understand the first part of this post, the latter often (not always) are not (let alone a lay person like the person I was having this discussion with).

This is not to imply any offense to PAs and LPNs (it's not their fault that their curriculum is more limited; it involves issues of access, cost of education, etc., and they are certainly in vast majority good and honest people who try their best and are valuable members of a healthcare team), and of course, exceptions exist for everything and I've encountered PAs who seemed to be MORE competent than some of my MD colleagues... and able to self-teach themselves beyond the instruction provided to them in PA school - but I'm just talking about whether or not it is wise for America to allow people with a much shortened education, to prescribe medications to patients. Sure, there is a supervision system in place, but I've seen multiple instances of this supervision being insufficient and scattered.

Finally, also part of this discussion was the issue of how intelligent doctors typically are. I sustain that it is credible that MOST (not all) doctors are likely to have an IQ of 120 or higher, which sits at the percentile #90, that is, the top 10% most intelligent people. The person I was speaking with, said that given many other professions that require high intelligence like top lawyers, various scientists, and even politicians, it wasn't credible that most medical doctors were to be included. However, in America, this top 10% would amount to 33 million people, and there are only 1 million doctors here (most of them, then, being 500,000 + 1) so there is plenty of room for all the other professions that require high intelligence.

Me, I'd say that MOST people who complete a 4-year college degree are likely to be at least at or above an IQ of 100. Most people who complete graduate school of various kinds are likely be at or above 110, and most people who complete the most demanding graduate schools, such as MDs, top lawyers, and PhD scientists, reasonably can be expected to sit at 120 and higher, given the constant need to absorb, organize, prioritize, process, and master a huge amount of high-level information and course work, in order to succeed in these demanding graduate schools and subsequent licensing examinations.

Again, I'm merely advocating for including MOST - not ALL - medical doctors in that intelligence range. The person I was spoking with advocated for MOST medical doctors NOT being included there (that is, MOST NOT having an IQ of 120 or higher), which again, I considered to be far-fetched.

This is not to say that medical doctors are infallible. Intelligent people can perfectly fail in various ways, and be mistaken either unintentionally or by dereliction of duty, or can be unethical, greedy, or even sociopathic; several successful medical malpractice lawsuits will attest to that (although only about 1% of medical malpractice lawsuits succeed). The applied science of Medicine in itself is not an exact science and is constantly evolving, and makes mistakes too. But to think that MOST medical doctors are not at 120 or higher of intelligence quotient, for me, is a stretch, particularly in a country like ours, where medical education is so selective and demanding.

Opinions? I'd be particularly interested in the opinion of one of our members here who is a very smart nurse, and will be open to her criticism, if she states that I'm being elitist and/or unfair.

@freedom8 @557 @Bowerbird

 

@CenterField, that’s a lot to unpack! Here are my random thoughts to facilitate more discussion.

I’d be surprised if 10% of general practitioner PhD’s could write the paragraphs you did on SSRI complexity without referencing printed material of some kind, let alone prescribe the “best” one for an individual without a refresher of some kind. I guess I don’t know how often such drugs are prescribed by GP’s, PA’s or practitioners as compared to a specialist.

That said, a PhD certainly would be better qualified to apply any information they would have to reference in their decision on which script to write. I think that’s your point, right? Not necessarily that a PhD would have a photographic memory, but that the PhD would have a stronger foundation in physiology to draw from, correct?

Specifically to the layman question, no, I don’t think Joe Blow with a PDR should be picking prescriptions.

Now the fun stuff—IQ! I don’t have a very good point of reference because not only do I not know my IQ, I don’t personally know anyone who knows theirs with certainty. Are MD’s mostly above average intelligence? Sure. At 120 or above? Not sure about that. I’ve known some that seemed pretty intelligent and some that seemed to be of average intelligence.

My first two years of college I spent with peers destined for med school, nursing school or PA programs. Some were friends from high school. In my opinion it looked like my friends chose occupations and subsequent level of education based more on how much effort they were willing to exert to get there than intelligence limitations. That said, the most successful doctor I know did graduate high school in my class with one of the highest GPA’s in the class. (Funny story about that if this thread progresses).

My wife’s family has some MD’s and DDS’s, and while intelligent I don’t think they all crack 120 IQ, but again, I don’t really have a frame of reference.

As far as being elitist and narcissistic, I think that’s a prerequisite for participating in PF! LOL. Joking aside, I don’t think meritocracy is elitism, and merit is what it appears we are discussing here since you’ve specifically mentioned common failings of intelligent people. Elitism would be claiming a more intelligent demographic deserved to have power or authority over another just based on intelligence (or education) alone.

Oh, I don’t care if a nurse practitioner or a specialized MD prescribed to me, I would find out everything possible about the drug and it’s nuances before taking it. But that’s just me and my Missouri (“show me state”) heritage eccentricity.

 

@557 I think if you were to measure professionally your IQ you'd be at least at 130, from what I know of your thinking process. Likely higher. You're welcome!

When you talk about some doctors you know who seem to be of average intelligence, I never pretended that ALL doctors are at or above 120. I merely said that MOST are likely to be there, in my opinion.

Hey, I just found a reference in an article. I suppose they got it from somewhere, from some sort of study although they don't say it:

https://www.mdlinx.com/physiciansense/the-biggest-career-mistakes-doctors-make/

"Doctors are smart. The IQ of the average American physician falls somewhere between 120-130, putting most doctors in the Very Superior Intelligence category on a standard IQ test."

Also found this:

"The literature suggests that average US doctor IQ is in the 120–130 range, as far as the USA is concerned. Two most important pre-med requirements are: Min. of 3.5 GPA in pre-requisite Science courses in undergrad college and scoring at least in top 40%-30% on MCAT (Medical school admission test). These two conditions are necessary, although not sufficient, to ensure an entrance into a US medical school to obtain an MD or DO degree. In order to become a licensed physician in USA you have to pass a number of standardized tests while attending medical school and thereafter, including but not limited to USMLE Step 1, Step 2, and Step 3. It’s hard to imagine a person scoring in top 40%-30% on MCAT and passing USMLEs and not being able to score above one standard deviation on standardized IQ test. One needs to have a minimum IQ of 115 (approx. one standard deviation ) to handle premed and med school curriculum and then pass a qualifying exam to become a physician in the USA."

This is from a post in social media. I don't know where the poster got this "the literature suggests" from. Another poster said "According to a ‘professions’ chart, it is 125 to 130."

I found a chart that shows medical doctors as the top in IQ of ALL professions. Apparently it comes from a study from the Center for Demography and Ecology of the University of Wisconsin-Madison:



Seems like the bar is slightly bigger below 120 than above it, but medical doctors seem to be the profession closest to having a majority above 120, so if this is accurate I was pretty close to being right.

Found this, too:

https://www.iq-test.net/what-is-the-average-iq-of-a-doctor-139.html

And this doesn't indicate if this is worldwide or just in the USA; one of my arguments was that medical education and licensing in the USA are more selective and more demanding than in other countries so most likely our MDs are at least a bit more intelligent than their counterparts in other countries (I'm sure other nationals here won't be happy with this statement), so if the data collection for the chart above is worldwide, I'd still sustain that in the USA we're likely to have a majority above the 120 mark.

As for the first part of your answer, I believe that SSRIs are prescribed by general practitioners in vastly bigger numbers than specialists. I do not believe that all practitioners know what I know about pharmacology, given that I am an MD-PhD and most aren't. But I think that medical students and medical doctors are at least equipped to understand the concepts.

My point is that the person I was having the discussion with, a lay person who most likely ignores ALL of it (given that I insisted in getting an answer and the person didn't provide any) pretended that he/she could pick an SSRI better than a doctor by reading the PDR.

Sure, someone can pick an SSRI. Eeny meeny miny moe is a method for picking something. But my point is that the method wouldn't be wise and well-informed. I give an annual lecture to my medical students on how to pick an SSRI, and I try to equip them with a RATIONAL, SCIENTIFC approach to guide the pick; not the PDR, and not eeny meeny miny moe.

A well-trained doctor (and my students get to be well-trained) is generally better equipped for this than a PA or a nurse practitioner.

 

I think people should be able to self prescribe

be smart to get a doctor's opinion, but the patient should make the decisions in the end

having doctors be the police of medications is just part of the war on drugs, people should not have to beg their doctors for the medications they want

hire a doctor to get their advice, not hire a doctor to get permission

 

Yay! I found a real study!

J.D. Matarazzo, S.G. Goldstein
The intellectual caliber of medical students
Journal of Medical Education, 47 (2) (1972), pp. 102-111

It is not available as a link but another study that references it, says that it concluded that the average full-scale IQ of medical students is 125!

QED!!!

And this paper by Matarazzo and Goldstein references 10 other studies, all with the same conclusion:

"Those authors found (~snip) that their sample of medical students performed similar to that of 10 other samples of medical student I.Q.’s from 1946 to 1967. The average Full Scale I.Q. of the medical students across the number of studies was 125, similar to the I.Q.’s of physicians at that time."

I guess I'm fully vindicated. I was right.

Oh wait, persistence pays off. I found a PDF of the Matarazzo and Goldstein paper!

https://www.gwern.net/docs/iq/1972-matarazzo.pdf

Indeed there are 10 studies listed there, all supporting my idea:



See, the average in ALL TEN studies is at least 122 and as high as 131. So indeed I was right in supposing that most medical doctors have an IQ of more than 120. After the unpleasant discussion with that person (which is why I walked away), it feels good to be right.

 

The principle of informed consent already establishes that a doctor is supposed to educate the patient on the risks and benefits of a medication and obtain from the patient the consent to give that medication to the patient. So the decision on whether or not to take the medication is actually the patient's (in the case of minors or incompetent adults in the legal senses, the custodian's or guardian's) and it is the doctor's responsibility to educate and guide the patient so that the patient can make a good decision.

Sorry, but "people" are not equipped to wisely "beg their doctors for the medications they want."

You seem to be equaling medical medications with drugs of abuse when you think that examining the competency of a doctor and licensing him/her to prescribe medications is merely done for the "war on drugs." By the way, licensing has existed for centuries, much before the "war on drugs."

And in virtually ALL countries, medicine is a regulated profession (for a reason) and being licensed to prescribe medications is a serious public health matter, given that not doing it right can literally kill the patient.

You know, your idea that people should 100% self-prescribe would unnecessarily kill a lot of people...

And the big pharma companies would prey upon the people, targeting them with advertising without a doctor being the guardian to ensure that it is not done inappropriately. For now, advertising ends with "talk to your doctor to find out if medication X is right for you." Without the license regulations, companies would then advertise as "just take it; our medication is great!!!"

Already, I do not like the practice of medication advertising directly to the lay public. Only the United States and New Zealand accept this practice.

 

I really probably have a very unrealistic view of what average intelligence is based on my life experiences. By luck or by design I’ve been around a lot of intelligent/successful people. I did the math awhile back on my high school graduating class and about 25% of that class had over $1M net worth by age 45. Many well over $1M. And nearly every one of them came from lower than middle class backgrounds. I don’t think that’s common.

It looks like you are certainly correct as you’ve found numerous sources verifying the 120 range claim.

The chart of occupations is cool. I remember seeing it somewhere before but had forgotten about it.

Oh, interesting thing about my wife’s family’s physicians. A couple did attend med school in Mexico.
Wouldn’t higher compensation levels for US MD’s compared to other countries influence the percentage of high IQ here as well?

Interesting. I guess based on the number of overall prescriptions written in the US I should have figured that out. I’m a bit overwhelmed at the rates the average American medicates.

Absolutely, med students and MD’s have the right tools for the job. Because they spent the time and money to acquire those tools.

That’s the nature of the forum. Lots of experts that can’t back up claims. I’m curious about the reasoning a non doctor could outperform a doctor in choosing an SSRI. I don’t follow the logic.

That is logical!

 

There is enough disagreement among medical practitioners and research on many drugs. But let us look at one issue alone - antibiotics

Worldwide there is a push for antimicrobial stewardship because we are running out of antibiotics. Balance that against all those people with colds and or the flu who DEMAND an antibiotic “so I will get better quicker”.

But about 20 years ago countries like Italy allowed people to buy medications over the counter.

it was NOT a success!

 

Australia has tightened the restrictions to the point where I can no longer get get any Free ECG Rulers or other pharmacy advertising - many reps cannot even buy you a cup of coffee.

Big Pharma HATES us Aussies.

Not only did we stop them pushing drugs but we have a thing allied the the PBS

https://www.pbs.gov.au/pbs/home;jsessionid=maub750joimjii4iapfv9igf

Every drug on there has been through approval, and been signed off for “benefit” which is in reality a subsidy to make the cost cheaper. This means there is essentially ONE buyer and that makes making profit hard.

 

no one has a issue with certain meds being prescribed, the issue is the prescription process is being abused

your example is a good example and why farmers abuse the system

I do not want to have issues sleeping, anxiety, pain, whatever and have to pay to beg my doctor for a medication I know would help me

 

Medications do help but also harm. Having a doctor overseeing if a given medication is more likely to help you than harm you is very important.

 

Australia is admirable. You guys do many thinks a lot better than what is done in America.

But I was hoping you'd opinion on the issue of the education of physician assistants and nurse practitioners (I don't know if equivalent professions exist in Australia and if they do, what they're allowed to do) versus the education of doctors.

 

yes, that is why we pay doctors for advice, we should not pay them for permission

if the gov feels something needs permission, they should pay for that as then I am not making the medical decisions, the government is

I encourage getting a doctor's advice, but after that, it's on you to decide what to do after getting that advice

too many prescription meds should be OTC

 

Your idea would lead to disaster as most people wouldn't pay for the advice; they'd just go ahead and self-medicate. Having to secure the advice of a licensed professional before securing the prescription is precisely why it makes sense to require it this way, so that people can't bypass the advice.

Frankly, I'm sorry if I say it a bit harshly, but your idea is one of the most far-fetched I've ever heard around here... which is to say a lot. It supposes that medical education is not really necessary... people can just self-medicate. To do it proficiently, the whole population then would have to go to medical school... which is impossible. And even that wouldn't ensure out-of-control and disastrous self-medication. Which is why the State Medical Board doesn't allow even doctors to prescribe to themselves and to their family members.

Not to forget the bias... Just like the saying "if a person decides to represent him/herself in court, the person has a fool for a lawyer" this self-doctor would have a fool for a doctor...

Now, the part about "the government should pay for that" I agree with, given that I'm generally favorable to government-sponsored health care for those who can't afford it on their own. But do realize that when one says "the government should pay for that," there is no free lunch. The government can only "pay for that" by taxing the citizenry. France, for example, has a spectacular universal healthcare system, arguably the best and most successful in the word... but also, France has much higher tax brackets for the citizens than the United States.

 

I disagree, you may not be able to make your own medical decisions, but I can

do you think you should have to ask permission to take aspirin, Tylenol, ect too

you seem to think the government should decide for you, I think people should decide for themselves

like I said, if the prescription system was not part of the war on drugs, I would agree with it

"Frankly, I'm sorry if I say it a bit harshly, but your idea is one of the most far-fetched I've ever heard around here... which is to say a lot. It supposes that medical education is not really necessary"

nope, in fact I said I encourage seeing a doctor for advice, then you decide based on that advice for yourself - I am even for requiring one to get advice before buying

 

Regarding the technical knowledge, I can, since I am a medical doctor and a very experienced one (last year I completed 40 years of practice).

But don't forget the bias... Just like the saying "if a person decides to represent him/herself in court, the person has a fool for a lawyer" this self-doctor would have a fool for a doctor...

You gave the example of aspirin and Tylenol. Are you aware that aspirin can kill you with a hemorrhagic stroke, and Tylenol can kill you with acute liver failure? Are you aware that Ibuprofen can lead to kidney failure? Even the list of over-the-counter medications, I think is fairly unwise.

But it is interesting that you mention two over-the-counter medications in this discussion... you do NOT need to ask a doctor for permission to take Tylenol and aspirin.

Still, I've seen cases of people who died of Tylenol poisoning, and I've seen cases of internal bleeding due to chronic use of aspirin, including fatal cases.

Like the person I was talking about, you THINK you can make your own medical decisions... but sorry, you can't do it safely because you lack the necessary knowledge to do it, if you are not a medical doctor. And I'm sure you aren't, because no doctor would have this far-fetched opinion, precisely because we know the risks involved, much better than a lay person.

Again, just like the person with whom I had the initial discussion, reading the PDR doesn't substitute for a full medical education.

 

yes, I agree, but see, you think you should decide for me, I think I should hire you for advice, and you should advise me, then I make the choice

I am aware that Tylenol can be abused, do you think I should have to get permission from you to take it - I can ask you about it, you can give me advice and then I act on that advice - that is the way it should be

people would be stupid not to seek medical advice

but a doctor that fears prescribing because of the government may harm patients too

you seem to not be happy with people coming to you and paying you for advice, you want to decide for them as well

 

the allergy medications I used to have to go into a doctor to get yearly are now OTC

the Albuterol I took, I can't get a refill without going into a doctor yearly - I stopped taking it and now take the OTC Primatene MIST

my doctor prefers the other, as do I, but unless my condition changes, I will just take the OTC

 

You are assuming things about me that I have not indicated in any way. I am for patient autonomy; just, I believe that the step of seeking advice must be mandatory (like it is now for all non-over-the-counter medications; actually like I said, if I were in control of the list of over-the-counter medications, I'd shrink it) because making it optional would lead to obvious abuse.

The "paying you" jab is silly, frankly. All professionals need to be paid; it's valid for doctors just like for all other professions. When I say it should be mandatory, I'm not talking about the pay issue. I'm talking about public health safety.

"People would be stupid not to seek medical advice" - unfortunately some people *are* stupid... which is not to say that we should make it easy for them to inadvertently harm themselves to save a few bucks. Not to forget the addicts. They would self-medicate for reasons other than stupidity.

 

and that is the point, your assuming things about me too, things I made clear in my posts that were not true

this is the problem with some doctors, they assume and deny drugs on those assumptions

 

Again, many of the over-the-counter medications actually shouldn't be over-the-counter. But yes, more access to affordable care should happen in America. Apparently the very attempt to ensure that sent conservatives into a furious frenzy...

 

What am I assuming about you?

 

you said I did not want medical advice and that was stupid as I did not know what you know, I made clear over and over I recommended paying for medical advice

what I am against is paying for permission, having to doctor shop to get a doctor that agrees with you in order to get said prescription

 

Quote the specific part where I said that you did not want medical advice.

 

But now I'm curious; if you don't mind disclosing, what exactly were the medications you had to doctor shop in order to finally get? List, please, if you don't mind.