Placebos work even when the patient knows it's a placebo ?

Cite for the subject claim :

Quote : “…But what if people were told, up-front, that they were getting a placebo and not an active medication? It stands to reason the placebo would have no effect. Right?

Quote : “Kaptchuk says placebos won’t work for every medical situation—for example, they can’t lower cholesterol or cure cancer. But they can work for conditions that are defined by “self-observation” symptoms like pain, nausea, or fatigue.”

Question : Has this research been replicated ? Can you please point me to some similar research ?

No, but I have some CBD oil (it says hemp oil) and I think it dissipates my anxiety when I wake up at 4 a.m. with the ‘what-ifs’. Even though I’m told it isn’t the right kind of CBD oil, or that CBD oil doesn’t actually do anything, I still think it works. Because I want it to help?

ISTM that if you’re told you’re taking a placebo and you still got better, then either you didn’t believe the person (and assume you got a real med instead) or for something like pain/nausea/fatigue, it was just time. That is, you would have felt better in 2 hours even if you took nothing.

Whenever I tell someone that X med fixes Y symptom and they reply ‘well, that’s just the placebo effect’, my usual response is ‘so what, if it works, does it really matter if it’s the pill or my brain making me feel better?’

I think you’re leaving out one other possibility.

You’re maybe too brainy to see it: you, and the writer of that article, and the doctor quoted in the article, too. Here’s the quote: He found that there was a dramatic and significant improvement in the placebo group’s IBS symptoms, even though they were explicitly told they were getting a “sugar pill”.

Imagine you have various symptoms, and a man in a white lab coat — who maybe has a stethoscope around his neck, plus a clipboard and everything — says he’s a doctor who, yes, hmm, reviewing a chart, taking notes, and hereby prescribing you these sugar pills. Being brainy, you might say what the article does: “were told, up-front, that they were getting a placebo and not an active medication.”

But now imagine you’re not so brainy; how do you describe the interaction? What were you actually told, up-front? When that impressive-looking doctor with credentials from Harvard Medical School or whatever explained that you should take these sugar pills, what did you literally hear and what did you in fact conclude? I’m not saying that you disbelieve the guy; it could be that you do believe the guy. “Huh,” you might say to yourself, “I guess I wasn’t getting enough sugar in my diet? Well, okay; you’re the professional, Doc; I believe every word out of your mouth.”

I’m fairly certain lots of ‘non-brainy’ people don’t trust doctors and may very well think they’re being lied to about the med their getting.

I think this is a similar result from a different group:

I’m with the Other Waldo Pepper for much of this; however, I think the impact of the doctor goes another way at the end.

“I feel sick and ill; however, this doctor is just giving me a sugar pill. If I were really sick, a doctor wouldn’t ethically be able to give me just sugar. The doctor clearly isn’t worried about how sick I am. Therefore, I’m not really that sick.”

Something else to consider: in a study you’re being monitored, cared for. Even if the pills are placebos, there’s someone who is taking your vitals, asking how you feel, what’s your condition is like. That by itself might be enough for someone to feel better.

Having worked in health care, this is a BIG thing. There’s something reassuring in knowing a “professional” is monitoring your symptoms, even if they aren’t actually doing anything about them.


Wow, I don’t get to move threads into GQ very often. But it looks like this is a factual (non-artistic) question, so there it goes.

How do you double blind a placebo test? Against what? Against people who are given the sugar pill and not told what it is?

Actually, the placebo, even if identified as such will work better if it costs more.


Your control is people who receive no treatment at all.

See this:

Apparently medications that would block the effect of a specific drug can also block effect of a placebo thought to be the drug administered

Cure: A Journey into the Science of Mind Over Body, by Jo Marchant, is a book about placebos (and other such phenomena).

One fair review of the book is here:

And that review links to another post about “Dr. Fabrizio Benedetti, a physician and clinical neurophysiologist who is one of the world’s leading researchers on the neurobiology of placebos.”

And this is the really fun bit: what if the reported placebo studies are false-positive results, subject to positive-result bias?

What we need is another study: Do placebo studies have a placebo effect :slight_smile:

What percent of those people who were told that even know what “placebo” means? Just like when the doctor told me he was giving me a ‘statin’ for my blood pressure.

One way of thinking about placebos is that they control for unaccounted factors. Like the care and attention received, regression to the mean (aka getting better over time), expectation bias, etc. In some cases, instead of a placebo, an established treatment could be used to compare with the experimental treatment, if the established treatment is well understood.

Placebo effect is often misunderstood or exaggerated in popular conception as an effect of the mind healing or controlling the body somehow based on the (false) belief that one is receiving treatment. But it is more accurate, I think, to think of it as data that points to an effect from a mechanism other than the one being tested.

Not only does a placebo work when it’s known to be a placebo; but – almost even more bizarre – the placebo effect is actually getting stronger over time.