Talk:Placebo effect

House of Lords - Science and technology - Sixth Report

I think this is a really thorough and neutral explanation of the placebo effect from the source the Gareth introduced us to. D. Matt Innis 05:33, 10 January 2009 (UTC)

Probably a little too late to absorb. Will look at it tomorrow; hopefully the forecasted blizzard doesn't get connectivity or power.

Reason for "might"

Perhaps I should copy the http://jme.bmj.com/cgi/content/full/30/6/551 reference from placebo. When I said "might", perhaps not in the most flowing way, I was thinking of their third case study, which I can make even more ethically complex. A patient presents with clinical depression, for which the clinician prescribes an appropriate antidepressant. The antidepressant is known to a 2-4 week delay before it takes effect.

The patient, however, reports immediate relief of symptoms. Now, unless there's a pharmacologic miracle, this fairly well has to be a placebo effect from a real drug. What are the ethical obligations to continue?

Take it a step further. Let's say the patient, a week later, starts complaining of known side effects from the drug. Now, what is the best ethical course? Keep the patient on a non-benign drug if it has shown benefit for the major complaint and the side effects are not intolerable? Change to a true inert medication, knowing the patient is suggestible?

Incidentally, do look at Talk:Sham treatment/Related Articles‎. Larry has some questions about the relationship among placebo, placebo effect, and sham treatment. All are related, but there's no strict hierarchy among them. Howard C. Berkowitz 05:58, 10 January 2009 (UTC)

I agree with all of that, but are you saying that, other than unconscious patients, there are times when the placebo effect does not occur? I know we aren't totally correct without the 'might', but how can we bring it out that, some believe that the placebo effect is part of all treatments based on the assumption that all human contact has a psychological impact. From the House of Lords above:

"The placebo effect has been described as the therapeutic impact of 'non-specific' or 'incidental' treatment ingredients, as opposed to the therapeutic impact that can be directly attributed to the specific, characteristic action of the treatment."

""...we all recognise the strong placebo effect in, probably, all aspects of medical treatment, whether they are conventional or not" (Q 155). "

D. Matt Innis 07:36, 10 January 2009 (UTC)

No, I don't assume placebo effect will occur in all cases. My experience and observations, and I think the literature in both pain management and psychopharmacology supports it, is that suggestion may have an effect, but frequently does not. It's very common to have to try several drugs before an effective one is found.

While the singular of data is not anecdote, I was having surgery for a pilonoidal cyst, back when night-before admission was common. The anesthesiologist visited me the night before, and I told him that while I didn't need or want preoperative sedation, not to use the then-current barbiturates as I was extremely insensitive. He laughed and said he'd just use more. The morning of surgery, the nurse came in with 300mg of pentobarbital, three times the normal dose. I was a little safety-concerned, but I took it. When I was wheeled into the OR, I was awake and alert, rather to the shock of the staff.

If the placebo effect always occurs, I should have been asleep. Since that was an enormous dose of an potent drug, if anything, there was a reverse placebo effect, but I don't remember fighting to stay awake. Howard C. Berkowitz 15:27, 10 January 2009 (UTC)

Ah, but you are assuming that it is the clinician (and I agree that is what we have written) that is the cause of the placebo effect, but the effects are not always the result of the clinician. It is whatever makes us believe that the intervention will work - the more elaborate the intervention, the more the placebo effect plays a role. You are saying that you 'believed' that you were 'extremely insensitive'. That could be an isolated anecdotal example of a placebo effect (though it could be something else as well). It's just that you suggested it to yourself. When a patient believes that a pill will cure their arthritis, it's effects are improved by the placebo effect. When they do not think it will cure their arthritis, its effects are diminished by the placebo effect. In other words, the placebo effect is always a part of any treatment, but that does not mean that the entire effect is the result of the placebo effect, only a variable part of it - depending on the patient. Most of the time the 'effect' is effective enough to overcome what amounts to 'negative beliefs', but in your case it wasn't. Even looking at it as a 'reverse placebo effect' is accepting that there is a placebo effect which is not always positive. That is what I mean when I say that some believe that the net effect always includes the placebo effect. D. Matt Innis 16:25, 10 January 2009 (UTC)

I just can't agree with that. Perhaps a Zen master could resist the effects of a general anesthetic or paralyzing agent, but quite a few drugs cannot be resisted. I have watched patients in chronic neurogenic pain despertately want relief, but the interdisciplinary pain management team might try half a dozen therapies, all with suggestion they would work, before getting any results. There was an excellent review on Medscape dealing with neurogenic pain, where a pain management specialist said that he wished he could know whether anticonvulsants, cardiac stabilizers used off-label, capsaicin, opioids, or other agents would work with a given patient, but, even with encouragement, they didn't work.

Beliefs rarely have much to do with infectious disease. If cellulitis is due to a resistant organism, until the right antibiotic is found or there is surgical intervention, I doubt very much that belief has much to do with outcome. Again speaking from anecdotal experience, I myself suggested cephalexin for an infection in my leg, and was surprised when it didn't work. A fluoroquinolone was then selected and did work. If staphylococci are methicillin-resistant, the approach isn't to reassure the patient and use more, but to get cultures and sensitivity, give vancomycin, and change again if the sensitivity gives different answers or there's no clinical response. Howard C. Berkowitz 17:07, 10 January 2009 (UTC)

Bibliography

Have to say I'm with Matt on this one; I think we have to assume that with just about any medical intervention for any condition there are likely to be at least effects of stress, anxiety, expectation and trust on the overall outcome, for many reasons, and possibly conditioned responses also. Psychological studies show all kinds of things have an effect on many symptoms - both objective (heart rate etc) and reported - ritual, authority, even the colour of pills - and their price and packaging. Doesn't mean that conventional meds aren't effective - just that a (quite large) part of their effect is attributable to placebo - and because in some conditions the placebo effect is so large there has to be some doubt about whether some conventionat treatments are any more than placebos. But let's not go there here, so to speak confusingly.

Susceptibility to infection is certainly affected by the HPA axis, through its effects on the immune system. Central defences to infection are also powerful, and include pyrogenesis - and these hypothalamic responses can be conditioned so they are at least capable of being modulated by expectation. Few medicines are effective in all cases - there are usually "responders" and "non-responders"; the same is so with the placebo effect. However, attempts to profile placebo "responders" gives, as Ben Goldacre put it, an astrology-type portrait that could pretty well be anyone. Anyway, to start maybe a next phase on this article I've been mining the literature, and you'll see on the Bibliography page the fruits so far. Please add anything that you think is germane there, and maybe we can expand the article from the evidence base? - and Howard - maybe you should have taken a placebo first time - maybe that would have worked :-) Gareth Leng 18:56, 10 January 2009 (UTC)

- I'm startled by how much has come out on the placebo effect in the last couple of years. I know there's been a sea-change underway in medical attitudes here though - not long ago in academic medicine the placebo effect was rather sneeringly dismissed as equivalent to no effect. Now it is realised just how important the patient-doctor relationship is to outcomes - and medical students are being taught how to speak to patients - and about time too. If this is all we learn from CAM, and it's probably not, it's an important lesson. Overprescribing is a massive problem, and we need to address it. The Lancet study in homeopathy has an important moral for conventional medicine - small trials are unreliable; it's a weak evidence base, and it seems likely that many treatments based only on small trials are placebo effects.Gareth Leng 19:21, 10 January 2009 (UTC)