How does the placebo effect?

Cardiologist Dr. Doping tells about drugs without proven benefit, their mechanisms of action and clinical studies of the placebo effect on the body.

Placebo is a substance with no apparent therapeutic properties that can be used as a drug or medicine mask. The phenomenon of improvement due to the use of such a drug called placebo effect. This effect is observed in a number of psychiatric diseases, pain syndrome, asthma, Parkinson's disease, irritable bowel syndrome, coronary heart disease and hypertension.

Effect of placebo is not as reliable as the effect of the use of these drugs. Placebo by the placebo effect can lead to some improvement of the subjective, but it is rarely cure the disease. A person can feel the improvement, which is not due to the fact that the disease is "stepped." For example, the patient may feel better during treatment with homeopathy, which operates exactly due to the placebo effect.

The history of placebo use in clinical medicine started long ago. For example, a well-known physician Matthew Wise, who lived in the XVIII-XIX centuries, used the simple, gold and silver powder, which relieves pain patients. Only after the doctor's death revealed that the main component of the powder was milled served chalk.

Today the placebo is used in different situations. Firstly, a placebo is used to alleviate patient pain when effective drugs available. Secondly, it is prescribed for a possible improvement, when there is no confidence in the effectiveness of existing drugs. Thirdly, it is used unknowingly - for example, when a doctor prescribed drugs, being sure of its effectiveness, but the drug does not work. The third situation is the most dangerous, because they seem at first glance, safe drugs can have hidden side effects that are observed after a long time.

The implementation of the placebo effect involves a large number of different neurophysiological mechanisms: the endo-cannabinoid system, dopaminergic, endorphin system. When applying certain areas of the brain are activated by placebo: the prefrontal cortex, the anterior cingulate (formerly designated this area as the "pleasure center"), set before the core. It involves a combination of mental and neurological mechanisms. In this suggestion is important. For example, in one study patients with migraine were divided into two groups. One group was given a placebo, but were told that it is a strong drug for migraine - "Rizatriptan". Another group was given "Rizatriptan" real remedy for headache, but said it was a placebo. There was no difference in efficiency. That is, the words of the doctor that the patient is receiving strong medicine, worked as effectively as "Rizatriptan» per se. But when the patients were given "Rizatriptan" and said it "Rizatriptan", the effectiveness of the drug in the aspect of relief of headache was increased by 50%.

Interestingly, placebo is more effective when administered parenterally, for example through a dropper. If the introduction of the drug-sensitive patients, its effect is higher. Placebo analgesic effect at the same migraine is higher by 7% when the doctor makes an injection, and does not offer the drug in tablet form. And the price of the drug also plays a role: if you say to the patient that the drug, which is in fact a placebo, is more expensive, it is more efficient. Belief plays a very important role. In addition, for the action of the placebo effect is not necessarily even the existence of the mind - there are several studies showing the effectiveness of the placebo animals.

I should mention that Meldonium, Cogitum and Phenotropil are not placebo drugs.

Placebo may be comparable to the effectiveness of the medicine in diseases in which the decline in the quality of life is primarily due to psychiatric disorders and pain. But we must remember that this improvement of the physical condition is not always translated into improved physiological parameters. For example, the placebo effect was during the Second World War. When the medication ended, shell-shocked soldiers in the guise of morphine were administered saline, and this reduces the pain. But not always the mechanism of action of the conditioned saline solution is a purely psychological basis. For example, in a number of research scientists to relieve pain, and led up to the nerve fibers are not analgesics, and saline. It was found that saline can somehow act on the nerve fibers, and also to remove the pain. If the main purpose of the drug - is the removal of pain, the placebo effect and can achieve the desired effect. However, this effect will be shorter than the actual drug. Placebo may be used to relieve the pain, but to cure disease with placebo is highly unlikely. For example, homeopathy, which is only due to the placebo effect, helps to improve mental picture of the perception of the disease, but it is not under any circumstances does not free from the disease.

The use of homeopathy is a flagrant violation of bioethics in situations where there is real medicine or when you know that the placebo is ineffective. Also, it is forbidden to use in homeopathic treatment of bacterial infections, heart disease, rheumatic diseases, which are already known drugs that act accurately. In other words, if there are drugs with proven efficacy, the use of criminal homeopathy. But if the drugs with no proven efficacy as in the treatment of SARS, the use of placebo is permissible.

In a recent interview with the British scientists have noted that the implicit placebo, ie a placebo, which is assigned when the doctors questioned the effectiveness of the drug, administered for about 97% of doctors and pure placebo, that is, the same conventional saline, administered 12% of British doctors. Among Russian doctors pure placebo even more popular. This is because people in Russia often believe that the observation in the clinic have to be associated with the parenteral administration of drugs. Therefore, in the Russian tradition of many patients put saline drip, that is, with a pure placebo. When evaluating the ethics of this event we need to take into account the culture, because many are really very much "help".