Have you ever felt better after simply placing a bandage on a wound? Have you felt more energized the moment after taking a bright red pill? If so, you’ve experienced a form of the placebo effect.
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A placebo is an inactive treatment that mimics an active therapy. The placebo effect happens when patients believe a placebo is effective. In turn, the placebo has an impact on their medical condition.
It’s not a real cure, of course. But the placebo effect demonstrates how sometimes the concept of healing can be as influential as the care itself.
How the placebo effect works
In truth, scientists don’t know exactly how or why the placebo effect works. But many studies suggest placebos trigger a process in the brain similar to what happens when you take certain pain medications. The chemical process is likely different, but there is a similar pain relief effect.
Environmental factors and your own preconceived notions also play a role. For example, optimists tend to respond more positively to placebos.
There are limits: A placebo can’t mend a broken leg or shrink a tumor. Still, for certain patients, it can positively affect the perception of pain.
“Patients may feel better because they expect to feel better, or they changed their behavior on that basis.”
When placebos are used
The placebo effect comes up most often in clinical trials to test new drugs or medical treatments. Participants in studies are often split into one of two groups: those who receive a placebo and those who receive the real treatment.
Researchers do this to “sort out the effect of the specific therapy itself compared to the therapy of being treated,” says clinical researcher Michael Lincoff, MD.
Just because placebos aren’t real doesn’t mean that they don’t have an effect. Sometimes, Dr. Lincoff says, even patients who receive the placebo in trials fare better than those who were considered for a trial but received no treatment at all for their ailments.
You won’t usually find placebos — at least in the form of sugar pills or other such mimicking treatments — beyond the research setting, though.
“To intentionally treat someone with a placebo is not really considered medical care,” Dr. Lincoff says.
However, he adds that certain routine parts of care might fit the loose definition of a placebo effect. For example, simply visiting a doctor’s office can be therapeutic for some patients, regardless of what comes next.
A variety of effects
The placebo effect doesn’t work on everyone, and even those who experience it show great variety. Some people might continue to thrive even after learning they’ve been taking a placebo, while for others, it will stop working once they know the treatment isn’t real.
Dr. Lincoff says it’s also hard to tell sometimes what is more effective: the placebo or the positive steps patients take at the same time toward improving their own health.
“Patients may feel better because they expect to feel better, or they changed their behavior on that basis,” Dr. Lincoff says. For example, if you receive medication for back pain, you might expect to feel better and therefore get out and walk more. The placebo is the motivation, but the real healing comes from your actions.
Your expectations influence the placebo effect
When you receive an injection or pill, do you expect your symptoms to improve? Those expectations are part of the placebo effect, too.
“Just being treated with medication makes people feel better,” Dr. Lincoff says.
There’s a flipside to the placebo effect, too: the “nocebo effect.” That happens when you believe a treatment will cause negative side effects and make you feel worse. For both the positive and the negative, patients are conditioned by what has happened in the past — and that influences how they act in the future, Dr. Lincoff says.
For good or ill, the placebo effect is a real phenomenon, both in research studies and in practice. Psychological processes have powerful influences on your well-being — sometimes as powerful as actual medication.