Placebo therapy

We often hear of the placebo effect in Parkinson's. Usually it is seen as a problem, because it makes it difficult to interpret the results of clinical trials. I see it differently. Placebos could be used as therapies in their own right, after all clinical trial after clinical trial has found that they work, reducing the symptoms of PD. We could even engineer them to maximise their effectiveness. And if they lose their effectiveness over time, there's an infinite number of new placebos to move to.


But surely it wouldn't work if you knew if was a placebo. 

Yes, you would have thought that, but an article in Scientific American, "Placebos Work Even When You Know", December 2010, reporting work by Kaptchuk et al., says the opposite: even when people know that they are on a placebo they continue to get benefit.

Anyway, I see no point in limiting ourselves to completely inert placebos. (Though it's hard to think of something which literally has no effect. Even water or sugar pills have an effect.)  I would use substances or actions which research and theory have shown to be safe and possibly to have a therapeutic effect, e.g. vitamin D, curcumin. I call these "therebos" (from THERapy or placEBO).

Successful therebos would generate more belief which would increase their efficacy.



Interesting, I didn't know that - it seems totally counter-intuitive, but then the brain's a bit of a mystery.

As an aside, a doctor once told me that placebos can have side-effects.


In the GDNF trial it's called brain surgery.  The hoped for extension to the trial becoming reality was very welcome as all will get the GDNF in the extension.  It will be interesting to see how effective the placebo was.

Indeed they can! I remeber one study which showwed how one PD drug increased the risk of headaches by 50%. Pretty bad. . . cept that the placebo increased the risk of headaches by 150%.


There may be a case for giving Homoeopathy a stay of execution after all.


Placebo effect is  a very interesting subject. and side effects can be as severe as a real drug.

.Did you know that research showed that the mind can influence and enhance the success of the drug by interpreting the strength of pill (colour, red stronger than white), or capsule (better and stronger than pill) or injection (stronger still )or the person who recommends/dispenses it to them (ordinary clothes,versus white coat)? After all everyone knows expensive cosmetics are  much better for your skin.....

And they did indeed find people successfully treated with a placebo even though the patient knew it contained only sugar. 

I was under the impression, however, that there was one drawback,  if you used a placebo over a longer period, the effect could become more uneven or more unreliable.


Hi ,


Google "placebo effect BBC "  for  the BBC Horizon series  (not currently available but will probably be repeated) on the subject and loads of  other refs.  Absolutely fascinating the really specific  physiological effects of placebos on the human body,  



Thank you for your comments.

Where do we go from here?

How do we get placebos/therebos to every PwP?

Do Parkinson's UK have any plans?


Hi everyone Really interesting discussion which we've been reading with interest. We are not funding any research specifically investigating the power of placebo for Parkinson's, but as you may be aware we are funding a clinical trial of a potential new treatment for Parkinson's called 'GDNF' - and half of the participants are initially receiving a placebo treatment. We will be announcing the results next year - probably in the autumn, and it will be extremely interesting to see how much the placebo effect comes into play. Read more about the trial here: The power of placebo can be extraordinary, and to a large extent medical (and complementary therapists)professionals already make use of it in the way they treat their patients. There was an interesting article about this on the BBC recently: We are actually planning to include an article all about the placebo effect in Parkinson's in the next issue of Progress - our free research magazine. So do look out for that in April 2016. See previous issues here: Best wishes Claire