A sick Londoner at the end of the 18th century had several treatment options. For example, you could go to a small shop in Leicester Square and for five guineas buy a device consisting of a pair of sharp metal rods that seemed to “pull” the disease out of the body. This method of treatment was by no means cheap. The device was called “Perkins tractors” after its inventor, Elisha Perkins, a self-taught physician from Connecticut. Perkins claimed to have treated George Washington himself. It was believed that the device had an effective effect in a number of diseases, such as rheumatism or various inflammations, due to the special alloy from which the rods were made. However, in 1799, the famous naturalist John Haygarth decided to test the effectiveness of the Perkins device by testing the imagination of patients. During the experiment, five patients suffering from chronic rheumatism were treated with the same rods as in the Perkins device, but made of wood. “All but one of the patients assured us that the pain was gone. One of them felt warmth in his knee and noted with satisfaction that it was much easier for him to walk. Another was relieved for nine whole hours. The pain returned when he went to bed. The third felt a tingling sensation for two hours,” Haygarth’s report says. On the second day of the experiment, real Perkins rods were applied to the patients, but the effect from them turned out to be the same as from a wooden fake. “Such is the great power of imagination,” Haygarth concluded.

The placebo effect is most often seen when people experience pain, fatigue, nausea, and depression. Brain scans of patients taking placebo show that areas capable of controlling stress and pain are activated. Brain scans showed how taking a placebo activated those areas responsible for controlling stress and pain. The US Food and Drug Administration (FDA) requires that scientists take into account the placebo effect when developing new drugs. To do this, during any clinical drug trials, some participants in the process are given not a test substance, but a placebo, without warning in advance who got what. The effectiveness of the tested drug is calculated by comparing the number of patients who felt improvement in both groups. In order for the drug to reach pharmacy shelves, as required by the FDA, this number in the group that received the real substance must be significantly higher than in the placebo group. However, it seems that the required ratio is gradually decreasing as the placebo effect spreads to an increasing number of people. Scientists claim that some common depression medications these days would not have passed repeated clinical trials.

This state of affairs worries the pharmaceutical industry. A number of drugs were rejected at the stage of clinical trials, while their development cost companies more than a billion dollars. So far, no one can answer the question of what is the secret of such an increase in the effectiveness of a placebo. Perhaps the results of recent research published in the journal Pain will help scientists get to the bottom of the truth. After comparing the results of 80 different trials of drugs against neuropathic pain, scientists from McGill University in Montreal concluded that the Americans were the reason for the emerging trend. It is the residents of the United States who, according to research, begin to feel better just from the fact of participating in clinical trials, regardless of whether they have taken a real drug or not. Source: BBC