
Beware the Nocebo Effect - sew
http://www.nytimes.com/2012/08/12/opinion/sunday/beware-the-nocebo-effect.html?_r=1&hp&pagewanted=all
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mistercow
One really important point about the placebo effect that a lot of people miss
is that a lot of it is not a real physiological change caused by the placebo,
but is a result of bias in both the subject and the experimenter. Over any
period of time, a person will have a great many variations in mood, pain, etc.
(which a subject is able to self-examine), and a great many variations of
biological function (which a researcher is able to measure). When those
variations correspond to effects that a subject or researcher has been primed
to expect, the subject or researcher is more likely to notice that effect.
This is simple confirmation bias. If you think trained scientists couldn't
possibly stumble on that kind of pitfall, you should read about N-rays[1].

This is just as likely to be true for the "nocebo" effect as for the placebo
effect. Dizziness, for example, is a very common symptom for people to
experience for myriad benign reasons. Orthostatic hypotension (head rush) is a
common cause of dizziness, and it is affected by a lot of minor factors like
hydration, vasodilation, how long you've been sedentary, how fast you stand
up, etc. This may happen to you three times in a week, and you'd never pay it
any mind. But if a doctor told you that a medicine you were taking might cause
dizziness, you _would_ notice it.

So to this extent, a placebo (or nocebo) effect can be accounted for with
absolutely no "mind over matter" style physiological change whatsoever. It is
plausible that some specific placebo effects like reduction/increase of pain
response, anxiety, and mood could actually be real psychological effects
involving suggestion. But if you hear of a placebo doing something and you
think "how could a belief in a placebo possibly have that kind of effect",
it's very likely that you are at least partly seeing mere measurement error.

[1] <http://en.wikipedia.org/wiki/N-rays>

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TheComedian
Though I understand that you aren't denying the placebo effect, I'm confused
about why you feel that a large amount of the placebo effect is due to bias.
After all, most drug trials are double-blinded and placebo controlled, so
surely in these trials the placebo effect is legitimate (assuming no
scientific fraud).

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Haplo
The placebo is actually there in double-blinded tests to remove any bias and
other factors related to the experiment. And no matter how good/legitimate the
experiment, any measurement pretty much always causes changes.

The actual effect of the placebo is usually at most a small portion of all the
factors that are measured by it. Of course this depends heavily on the
experiment in question and some drugs (like psychological ones) have a higher
placebo effect than others.

A lot of people seem to have the idea that the placebo effect is very big for
medication outside of experiments - but most of the time it's very small to
non-existing.

~~~
Semaphor
Considering the placebo effect (unless you think bioresonance therapy is true)
cured me of several allergies, I'm pretty happy with how strong it is:)

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mistercow
Or your allergies just went away as you got older, and you attribute that to
the placebo effect.

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pygy_
There are complex interactions between the nervous and immune systems.

I don't think that anything has been demonstrated regarding allergies, but I
wouldn't rule out a therapeutic effect in this case. The absence of evidence
is not an evidence of absence.

~~~
Semaphor
I must say I honestly don't know if they were allergies in the medical way.
For quite some time I couldn't drink large (>1L/week) of milk while milk
products were fine. I always called that an allergy and only learned much
later that it's not;)

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typpo
The nocebo effect is quite powerful. I'm 22 years old and was in chronic pain
for a year. I had trouble doing simple things like opening doors.
Understanding nocebos helped me cure my carpal/cubital tunnel and thoracic
outlet problems.

After wasting a lot of money on ergonomic setups and doctors I read Aaron
Iba's post on how he cured his RSI [1]. One of my takeaways from subsequent
reading and research was that the nocebo effect played a huge role in how I
associated computer usage and programming with pain. When you expect an
autonomic symptom, you are much more likely to experience it.

Since treating myself with this in mind, along with other techniques such as
those outlined by Aaron, it's been a couple months since I've been in pain
from using a computer.

[http://aaroniba.net/articles/tmp/how-i-cured-my-rsi-
pain.htm...](http://aaroniba.net/articles/tmp/how-i-cured-my-rsi-pain.html)

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Jaecen
The last sentence: "Words are the most powerful tool a doctor possesses, but
words, like a two-edged sword, can maim as well as heal."

I would really like to get one of those swords that heal on one side and maim
on the other. Think of the possibilities!

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tzs
Part of this I suspect is that people might already have the symptoms of the
side effect but not know it. Almost all of us have random coughs and sniffles
and aches and pains, but don't notice them.

Think, for instance, of those times when you've heard a friend or co-worker
cough several times over a few minutes and you ask if they are alright, and
they have no idea what you are talking about because they were not aware that
they had coughed.

When you tell someone the pill they just took might have a side effect of
making them cough, they are going to notice those random coughs that they
normally ignore, and attribute them to the pill.

~~~
smashing
In some strange way, the placebo effect has its own placebo effect. People
will tend to not voice their issues because they wish to stay on track for
their treatment, get out of the doctor's office and on with their life.

After all, a guy isn't going to just blurt out erectile problems if he is led
to believe by the expert through the error of omission that erectile problems
aren't a side effect. Its just too embarrassing.

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dag11
The example of the suicide attempt with fake medication causing the subject's
blood pressure to drop to dangerously low levels got me thinking.

If the belief that (s)he would die was almost enough to actually kill him/her,
would it be possible for someone to end their own life with just their
thoughts alone?

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mistercow
There really isn't enough information in that anecdotal retelling to make
heads or tails of it, but from that limited information, I'd say that person
probably just had a panic attack. Panic attacks cause a spike in blood
pressure for most people, but for some people the opposite will sometimes
happen. I used to have them from needles, and in high school I went to the ER
for suspected meningitis. They had me hooked up to monitor my vitals, and when
a nurse stuck me with an IV, the room suddenly filled up with panicking
medical personnel because my blood pressure hit the floor.

So my guess would be the subject in question took a bunch of pills, freaked
out and went to the ER, and then had a panic attack because they thought they
were going to die.

But to answer your question, I think that if you can, by panicking, alter your
blood pressure (up or down) enough to kill yourself, that just means you had
some pretty messed up cardiovascular issues. You wouldn't call that "killing
yourself by thought alone"; you'd call it "dying of cardiovascular disease".

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cperciva
I'm not a doctor, but your case sounds more like a vasovagal response than a
panic attack.

(I have an interesting vasovagal response -- I can draw my own blood just
fine, and a nurse can draw my blood if I don't watch; but I've fainted from
watching a nurse draw my blood.)

~~~
mistercow
Interesting. I had not heard of that, and since I have anxiety disorder (I
have had panic attacks about other things), I always assumed it was just part
of the same thing, and it certainly feels similar. I guess that makes sense
given that panic attacks are a feedback loop; maybe the vasovagal response was
just a trigger.

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AddictionMyth
I think that drug addiction could be partly the nocebo effect. After all, we
are told repeatedly as children: beware drugs, because you might find that
once you start taking them, you are unable to stop. Then all sorts of terrible
things will happen. So for some kids, this may seem like the perfect
opportunity! <http://AddictionMyth.com>

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rafski
I always wondered to what extent the official warnings on cigarette packs
contributed to the illnesses presented on them actually materializing.

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vishaldpatel
Chalk one up for thinking positively.

