Why do placebos work?

The placebo effect

Dr. Barsky laughed: “Well, when you think about it, there are a lot of things that we do that aren’t directly curative that make a difference -- vitamin pills, iron pills, cold packs, heat packs, giving antibiotics for a viral infection because the patient really wants it.”

And it’s not just that the patient imagines feeling better. Dr. Kaptchuk showed Spencer brains scans of patients who responded to placebo treatment who were in pain: “We actually see part of the pain matrix being activated that would change this sensation of pain,” he said.

Just the act of taking a pill, even a fake one, can coax the brain into producing its own helpful chemicals. “In fact, we know that giving the pill in the context of the health care encounter activates neurotransmitters,” Dr. Kaptchuk said.

“Something chemically is happening? That’s amazing to me,” Spencer said.

“It’s really amazing to me [and] I’ve been in this business a long time!” Dr. Kaptchuk laughed.

Neurologist Alberto Espay of the University of Cincinnati, who specializes in Parkinson’s disease, says, “I know that the phenomenon of my patients changing by virtue of nothing else than their expectations, is real.”

He says drugs used in Parkinson’s help the brain make dopamine. Turns out, placebos do, too.

“And this can be measured objectively? Measurable changes within the brain?” Spencer asked.

“Very much so.”

Bob Walton has lived with Parkinson’s for more than a decade. Dr. Espay enrolled Walton in a study supposedly comparing an expensive drug to a cheaper one.

“I actually felt a little better after I got the expensive one,” he said.

Well, guess what: “He did an interview with me about an hour-and-a-half after it was over with,” Walton recalled. “And he said, ‘They were both saline solutions.’ Both were placebos.”

And of course, there was no price difference at all. Yet the patient who thought they’d taken the more expensive drug felt more improvement. Not only did the supposedly expensive drug do twice the job, it did just as well as a real Parkinson’s drug.

“So they thought that because it was expensive it has to be good?” Spencer asked. “And that alone can affect things physiologically?”

“It does,” Dr. Espay replied.

The lesson here, says Dr. Espay: When patients believe in their medications, those medications just may work better.

Spencer said, “Now, to do your experiment you had to mislead people. How did you feel about that?”

“Terrible!” Dr. Espay laughed.

In fact, outside of clinical trials like Dr. Espay’s, the American Medical Association frowns on deception in treating patients. “Patients cannot be given a placebo without informed consent, and [being] told clearly, transparently what it is,” Kaptchuk said.

But given Linda Buananno’s success with placebos for her IBS, it may not matter if patients know … which raises an interesting question:

“I think the next step is, how do we concretely use placebo effects in clinical practice?” Kaptchuk said.

Dr. Barksy believes there are some ways in which patient may still get the benefit without being deceived: “You tell the patient, ‘We’re gonna give you the active medicine, but on some days you’re gonna get a placebo. And if that were to work you would then lessen the chance of addiction, tolerance. [And] it’s cheaper.’”

Meanwhile, Buananno’s symptoms are back, full force, but she has an appointment with Professor Kaptchuk. “I’m possibly gonna go on placebos again and see what happens,” she said.

“It seems so strange to hear somebody say, ‘I’m going on placebos,’” Spencer said. “It’s like saying, ‘I’m about to start taking nothing again. I’m really excited!’”


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