Because they demonstrate the influence of mental states—attitudes, beliefs, and expectations—on physical results, placebo effects have been dubbed the "crown gem" of psychosomatic medicine. Indeed, clinical studies have shown that placebos can have positive effects on symptoms of disease, even in those cases where there is no active treatment available. The most common example is the effectiveness of placebos in alleviating pain; however, placebos also have been shown to affect the progression of disease, the frequency of infections, and the severity of symptoms after trauma or surgery.
The placebo effect has been observed since ancient times. It was first described by Plato in a discussion of the effects of prayer: "Placebos are used in medicine to treat patients who do not need real medicine but rather its appearance," he wrote. "For example, if a man believes he is sick and needs a doctor, but all that happens is that the patient's mind has made him feel better by believing he is sick, then we say that the place-bo has healed him."
Modern research into the placebo effect began in the 1950s when researchers started testing drugs against placebos to see if their effects were due to magic instead of the drug itself. Studies have shown that placebo treatments can have beneficial effects on symptoms of disease ranging from morning sickness to arthritis.
The placebo effect occurs when symptoms improve despite the use of a nonactive medication. It is thought to be caused by psychological variables such as expectancies or classical conditioning. The placebo effect has been shown in studies to alleviate symptoms such as pain, weariness, and sadness. It has also been shown to increase the amount of food we eat and reduce how often we vomit.
Placebo effects have been observed in many clinical situations including treatments for asthma, arthritis, depression, epilepsy, fever, heart disease, hypertension, insomnia, obesity, psychosis, stroke, and tuberculosis. Placebos can also enhance the effectiveness of other medications taken by the patient. For example, if a patient takes insulin and receives supportive therapy (placebo treatment) at the same time, then the patient's blood glucose level will likely decrease.
The placebo effect should not be confused with nocebo effects. Nocebo effects occur when taking a placebo drug leads to worsening of existing symptoms or development of new symptoms. For example, patients who take placebos for headache relief may find themselves with more headaches when compared with those who simply relax and enjoy a massage.
Research on placebos shows that they are very effective when used properly by physicians and patients. However, the effect does depend on how it is presented to the patient.
Despite the fact that placebos contain no actual medication, studies have shown that they can have a range of physical and psychological impacts. Changes in heart rate, blood pressure, anxiety levels, pain perception, weariness, and even brain activity have been seen in placebo group participants. The effects are so powerful that researchers have suggested that placebos may be used as a treatment for diseases such as diabetes, cancer, and HIV/AIDS.
Placebos work by triggering the body's natural healing processes. They can also act on other mind-body mechanisms such as hypnosis, meditation, and prayer. Placebo effects have been observed in patients who believe they are receiving real medical treatments and therefore expect them to work. This suggests that placebos can help spur people who suffer from disease-related depression and anxiety to feel better.
Studies have shown that placebos can reduce pain, fever, nausea, and vomiting associated with medical procedures, add to a person's sense of well-being, and improve their quality of life. The same is true of placebos when administered intentionally for therapeutic purposes - they can provide relief for symptoms such as headache, insomnia, irritability, and muscle aches without any known side effects or complications.
In conclusion, placebos can have a wide range of effects on the body and mind.
The placebo effect may also have a psychological conditioning component: if someone benefits from an intervention, that person begins to link that intervention with a benefit. With further exposures to the intervention, the link, and therefore the benefit, may become stronger. This is known as "conditioning" or "learning." Placebo effects can be used in therapeutic settings to treat illnesses such as asthma, arthritis, and diabetes or simply for pain relief.
In addition to benefiting patients physically, placebos can also help patients psychologically. For example, if a patient believes that a placebo will make him feel better, it can have a beneficial effect even though the pill is not actually doing anything physical to the body. The patient can experience a sense of relief just by thinking that taking the pill will help him get over his problem. In this case, the placebo effect is being used therapeutically rather than accidentally because the patient's belief that the placebo will work helps him get over his depression or anxiety faster than if the pill wasn't being used at all.
It is important to note that the placebo effect can also have negative consequences. For example, if a patient is using a placebo instead of seeking proper medical treatment, this could lead to missing out on necessary interventions which could potentially cause more problems down the road.
Placebos are commonly used in clinical trials to determine the effectiveness of new drugs or other treatments.