Biology 103
2003 First Paper
On Serendip

Placebo: the word is Latin for "I will please." Originally it started the Vespers for the dead, often sung
by hired mourners, and eventually "to sing placebos" came to mean to flatter or placate (1). Later, the
term was used for any kind of quack medicine. Today, it is a medicine that has no value in itself, but
improves a patient's condition because the patient believes it to be potent.
Belief in a swallowed sugar pill or saline injection has been shown to produce real reactions. 80% of
patients given sugar water and told it is an emetic respond by vomiting (1). People often show an
allergic response to something they believe they are allergic to, even if it is only plastic flowers. Does
this strong reaction hold true for more serious medical conditions, then?

There are three explanations as to why placebos may work. The first, called the opoid model, says that
the positive response is a result of endorphins released in response to swallowing a pill, etc. The
second is the conditioning model, which holds that the important factor is not the medicine, but contact
with a medical professional. Because patients are used to getting better after they go into a doctor's
office and talk to someone in a white coat, they are psychologically conditioned to get better after
contact with the medical environment. The last is the expectancy model, in which patients improve
because they expect the placebo to have a certain effect.

There are even more arguments, though, as to how the placebo effect has been exaggerated or
fabricated. Some studies include additional treatment along with the medication, so simply being in a
study may produce results (1). Some studies on placebos often show similar rates of success for a drug
and a placebo, but do not include a control in which no treatment is used. In such studies, it is
impossible to tell what improvement was actually due to the placebo and what would have happened
anyway (3). Patients may also tend to report improvement because they think this is what is expected.
This is especially true with poorly designed response forms with more options for improvement than
worsening. Many illnesses, like colds, improve by themselves given time. Others, like depression and
chronic pain, fluctuate. Thus improvement in these types of illness might well have happened without
any medicine or placebo. Indeed, there are some who argue that antidepressants have value only as
placebos, and should be debunked (4).

Other problems exist in testing placebos' effectiveness. They cannot be used in studies on life-
threatening or degenerative illnesses, since taking an inactive treatment rather than a real one could do
patients real harm. Tests in which patients know they may be taking placebos show different results
from tests in which they are given only a drug. Here the same effect is seen with negative effect -
people react to the treatment they think they are getting. Patients have been shown to react less to real
medicine if they know there is a 50% chance they are actually getting sugar pills (1).
The first report on the placebo effect was made in 1955 by Henry K. Beecher. German researchers
recently took a closer look at the 15 studies on which Dr. Beecher based his report, and found that
much of the "evidence" in favor of placebos was inaccurately reported in his report. For example, he
reported that 30% of patients in one study improved after taking a placebo, but neglected to mention
that 40% worsened (3).

The argument began within the medical community, but awareness of the debate has spread to laymen.
Humor writers at The Onion (5) recently wrote an article joking that the FDA had approved a
prescription placebo called Sucrosa to treat everything from bipolar disorder to erectile dysfunction.
And despite the controversy surrounding placebos, they are also widely present in medical practice. It
is common, for example, for doctors to prescribe antibiotics for flu and viral colds (1). They know full
well the treatment can do nothing to cure the cold, but the purpose is to placate the patients. In this
case the use of placebos is actually harmful, since needless use of antibiotics diminishes their potency by
creating resistant bacteria (2).

Does the effect really work, then? Are doctors just wasting patients' money on useless medicines?
Maybe the "effect" is nothing more than a result of skewed studies. Some conditioned responses are
quite provable, but showing what caused an improvement in a patient taking a placebo is nearly
impossible. We can prove that Beecher's study was flawed, but continuing studies will no doubt
continue to alternately support and debunk the theory. The reality is probably this: hey, it's the medical
community. They'll be debating for many years to come.

References

1) The
Mysterious Placebo Effect, an article from Modern Drug Discovery
2) The Mysterious Placebo, from the
Skeptical Inquirer
3) The Placebo Effect: Fact or Fiction?
4)
Listening to Prozac but Hearing Placebo: A Meta-Analysis of Antidepressant Medication, an article
from Prevention & Treatment
5) The Onion, FDA Approves Sale of Prescription
Placebo


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