How Does The Placebo Effect Work?

A placebo is a phony drug used to test the efficacy of real drugs in clinical trials… but here’s the weird part. Sometimes, placebos can make patients better. How? Why?

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Episode Transcript

Speaker 1 (00:02):
Welcome to brain stuff. From how stuff works, everybody, I'm
Christian Seger, and this is brain stuff. You have surely
heard of placebos, their phony drugs that real drugs are
tested against. But have you ever wondered how someone could
be fooled into thinking they've received a powerful chemical compound

(00:22):
when all they've been given is in a inert sugar pill. Well,
fortunately some researchers have wondered too, and they've come up
with some really astounding answers. Placebo actually means I will
please in Latin, and they take their name from mourners
who are hired to be sad at funerals. Back in
medieval times, the mourners were fake in the term eventually

(00:45):
came to be applied to fake drugs. As many as
half of all physicians admit to having used placebos in
their general practices, usually in the form of vitamins. Back
in the day, physicians used placebos when they had no
other avenues of treatment available. They had nothing to lose,
and neither did the patients, so you know who cared.
Placebos became a standard component of the double blind study,

(01:09):
where participants are split into groups that either get the
drug or get the placebo. The logic there is that
if the real drug elicits a stronger response than the
fake drug, you know, the placebo, then it's proven successful.
Bingo it works. The thing is, some researchers noticed that
a lot of people in the double blind studies who

(01:30):
received placebos still had positive reactions to them. As many
as one third of all people respond favorably to placebos.
And let's recap here. Sick people are given fake drugs
like a sugar pill, and then they get better as
a result. This is not supposed to happen, so studies

(01:50):
were launched to find out what was going on. One
two thousand four study in Michigan gave participants a painful
but harmless injection in their jaws. Then they were given
a saline injection they were told was a pain reliever.
Saline has no pain relieving properties, hence it was a
placebo injection. Astoundingly, the researchers found that the pain levels

(02:11):
went down in everyone in the study following this injection.
When viewed through a PET scan, the researchers found the
participants brains had released endorphins, the body's natural painkillers, So
a fake injection elicited a genuine biological response because of
the placebo. The people's pain decreased, not just in their minds,

(02:35):
but in actuality. And it's not just saline injections and
sugar pills that can elicit a placebo effect. What conventional
medicine considers sham treatments like say acupuncture, have been shown
to at least produce a placebo effect, and even sham
sham treatments can to like for instance, in tests of

(02:55):
acupuncture that use retractable needles. Even more sounding is the
no sebo effect. Not only can fake drugs and treatments
produce a positive response, people can suffer from negative side
effects from placebo's two. So what is going on here? Well,
researchers explanations typically fall into two camps. The subject expectancy

(03:19):
effect where people know what the outcome should be and
unconsciously conform to that expected outcome, and classical conditioning like
Pavlov's dogs, but instead of salivating at a bell, we
experience relief through what we think is a drug. The jury, however,
is still out on what exactly is behind the placebo effect. Ethically,

(03:41):
there's a wrestling match going on. On one hand, the
idea that people can heal through the power of their
own bodies rather than through powerful drugs that often have
undesirable side effects. Well, it's a good thing. On the
other informing patients truthfully is a tenet of modern medicine,
and placebo's require pretty much outright lying by doctors. So

(04:03):
what to do. Some clever physicians have figured out a loophole.
They can offer a placebo as a cure to a patient,
but tell them they're not sure how the drug works.
All that's missing is the wink and the nudge. Check

(04:23):
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