Types » Placebo Effect
Placebo Effect
What is a placebo?
   A placebo (pluh-see-bow) is a substance or other kind of treatment that
   it’s not a medicine. The person getting a placebo does not know for
   sure that the treatment is not real. Sometimes the placebo is in the
   form of a “sugar pill,” but a placebo can also be an injection, a
What is the placebo effect?
   Even though they do not act on the disease, placebos seem to affect how
   person’s symptoms as a result of getting a placebo is called the
   placebo effect. Usually the term “placebo effect” speaks to the helpful
   effects a placebo has in relieving symptoms. This effect usually lasts
   unpleasant effects that happen after getting a placebo are sometimes
   effects. This means that the person taking the placebo may experience
   that he or she is getting a strong medicine, the placebo may be thought
   to cause the side effects. The placebo does not cause any of these
   placebo helps change the symptoms, or change the way the person
   Some patients can have the placebo effect without getting a pill, shot,
   doing something else they believe will help. That type of placebo
How are placebos used?
   Placebos may be used in clinical trials. Clinical trials are research
   people in the study may be given a placebo, while others get the new
   treatment being tested. The main reason to have a placebo group is to
   The placebo looks, tastes, or feels just like the actual treatment, so
   outcomes. The placebo control makes it possible to “blind” patients and
   People in a study that uses a placebo should always know that there’s a
   chance they could be getting a placebo. It’s not OK to give someone a
   placebo. Please see our document Informed Consent for more information
   Those who get placebos in medical studies serve an important role.
   the treatment being tested. The placebo group provides an important
   unless there’s a placebo group and those people get better too. On the
   also happen to people in the placebo group.
How does the placebo effect work?
   convincing proof that the placebo effect is a real effect. But there
   are studies showing that the placebo effect is real. For example,
   scientists have recorded brain activity in response to placebo. Since
   many scientific tests have shown the placebo effect, it’s one way we
   Some scientific evidence suggests that the placebo effect may be partly
   Many think the placebo effect occurs because the patient believes in
   placebo, it doesn’t mean the person’s illness or symptoms were not
   hormones drop. Taking a placebo may change their perception — for
   What’s commonly called the placebo effect even plays a role in
   This suggests that past experiences also play into the placebo effect.
   In one study that looked at the placebo effect in pain relief, one
   days, both groups were given a placebo that looked like the real pain
   response when they were given a placebo later. Those who had not gotten
   they got the placebo, even though they were told that they would. This
   placebo effect.
   after a placebo, is still being studied. Researchers believe it may be
   not have viewed their efforts as placebos. But their healing powers may
   Because placebos often have an effect, even if the effect doesn’t last
   long, some people think that the placebo produced a cure. But placebos
   tumor shrinks, placebos have very little, if any, effect.
   Still, placebos clearly can help reduce certain symptoms such as pain,
   placebos were sometimes given by doctors out of frustration or
   doctors polled said that they used a placebo when they felt that it
   Sometimes if the placebo looks more real, the person may think it’s an
   some people, an injection may have a stronger placebo effect than a
   Some believe that placebos seem to work because many illnesses improve
   taking a placebo. Just as natural endorphins may relieve pain once they
   scene much as it would to something it actually sees. A placebo may
   may simply be a placebo effect. If the patient believes in the
   not a placebo effect.
   thought of as placebo effects, some short-term effects are affected by
   There’s still much to find out about the placebo effect and all the
   ways it may work. Researchers agree that the placebo effect cannot cure
Other things that can add to or be confused for the placebo effect
   with the placebo effect. These are effects that can cause a study to
   report that a placebo (or even a treatment) had some effect when in
   Along with the placebo or nocebo effect, incidental events (unrelated
   effects that might have happened without the placebo) might also be
   linked to the placebo because of their timing. For example, a headache
   or rash that happens soon after taking a placebo could be caused by
   something else entirely, but the person might think the placebo caused
   start feeling better after taking a placebo, that improvement may be
   thought to be due to the placebo.
   to what’s thought of as the placebo effect. Even in serious conditions
   the effect of timing, noted above. A person who was taking a placebo
   that the placebo had some effect. And a self-limited illness that goes
   away completely on its own at such a time might have the placebo-taker
   know they’re getting placebos will know that their headache is not due
   Studies comparing placebo to no treatment found that patients were more
   in their comfort if they were on placebo. This was observed when the
   the clinical trial. This can affect outcomes for both the placebo and
   placebo, are more likely to leave the study before it’s over. This
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