Why 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?

Learn more at HowStuffWorks.com:
http://science.howstuffworks.com/life/placebo-effect.htm

Share on Facebook: http://goo.gl/9UihP8
Share on Twitter: http://goo.gl/PZvgST
Subscribe: http://goo.gl/ZYI7Gt
Visit our site: http://www.brainstuffshow.com

You’ve surely heard of placebos – they’re 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 when all they’ve been given is an inert sugar pill?

Placebos mean “I will please” in Latin and they take their name from mourners who were hired to be sad at funerals back in medieval times. The mourners were fake and the term eventually came to be applied to “fake” drugs.

Placebos became a standard component of the double-blind study, where participants are split into groups that either get the drug or get the placebo. The logic is that if the real drug elicits a stronger response than the fake drug (the placebo) then it’s proven successful. It works!

The thing is, some researchers noticed that a lot of people in double blind studies who received placebos still had positive reactions to them. As many as a 1/3 of all people respond favorably to placebos. And let’s recap here: Sick people are given fake drugs, and get better as a result. This isn’t supposed to happen.

So studies were launched to find out what was going on. One 2004 study in Michigan gave participants a painful but harmless injection in their jaws. Yow. 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 went down in EVERYONE IN THE STUDY following the injection! When viewed through a PET scan, the researchers found the participants’ brains had released endorphins, the body’s natural painkillers.

Because of the placebo, the people’s pain decreased not just in their minds, but in actuality.

Even more astounding is the nocebo effect: Not only can fake drugs and treatments produce a positive response, people can suffer from negative side effects from placebos too.

So what’s going on here? Well, researchers’ explanations typically fall into two camps: the subject-expectancy 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, 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 is a good thing, as Martha Stewart would say. On the other, informing patients truthfully is a tenet of modern medicine and placebos require pretty much outright lying by doctors.

So 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.

SOURCES:

http://science.howstuffworks.com/life/placebo-effect.htm/printable

http://www.nytimes.com/2012/08/12/opinion/sunday/beware-the-nocebo-effect.html?_r=0

http://www.newyorker.com/magazine/2011/12/12/the-power-of-nothing

http://www.bmj.com/content/337/bmj.a1938.full

http://link.springer.com/article/10.1007%2Fs11606-007-0332-z

http://academicdepartments.musc.edu/humanvalues/pdf/Placebo.useinclinicalpractice.pdf

http://www.amednews.com/article/20120618/profession/306189942/7/

http://www.ama-assn.org/ama/pub/physician-resources/medical-ethics/code-medical-ethics/opinion8083.page

http://www.ncbi.nlm.nih.gov/pubmed/11772700

http://www.jneurosci.org/content/25/34/7754.full
Video Rating: / 5