And perhaps the most astonishing thing is that the patients were told that they were taking a placebo—and it was still working. In fact, many of the patients pleaded with the researchers to be given more of the dummy tablets, but, for ethical reasons, their request was refused.
The 74 cancer survivors who took part in the placebo study were all suffering from moderate to severe fatigue, and they were either given an 'open label' placebo—which means they were told beforehand—or they continued their current treatment for their tiredness.
The Harvard Medical School researchers, who ran the study, instructed the participants to take two placebo pills twice a day for three weeks. At the end of the three weeks, the other participants, who were having standard treatment, started taking the 'open label' placebo pills instead, and the first group stopped taking the pills, and didn't resume standard treatment.
By the end of the trial, most of the participants reported a 'significant improvement' in their levels of fatigue, and these improvements were still evident even three weeks after stopping the placebo treatment.
"The effects of the placebo pills on fatigue were so dramatic that we had a number of the study patients ask if they could be given more of them, but, for ethical reasons, we were unable to do so," said lead researcher Teri Hoenemeyer.
The fact the participants knew they were being given a placebo didn't make a difference to the outcome. "Fooling or deceiving patients may be unnecessary for placebo effects to produce benefits, with automatic neurological processes being a possible mechanism for the effects. This has revolutionary implications for how we might exploit the power of placebo effects in clinical practice."
Cancer patients often report that chronic fatigue is the most distressing condition they must endure after treatment has finished, and one that they rank as being worse even than nausea and pain.
Conventional medicine has little to offer to help treat extreme tiredness, and the only drugs that can be prescribed come with a range of side effects that include panic attacks, psychosis and even heart failure.