To the extent that our brains control our bodies, forces that modify our brains also modify our bodies.  Hence, when one believes something strongly, the consequences of that belief could produce a measurable clinical effect.  If one strongly believes that vitamins improve energy, then one’s energy can measurably increase by taking vitamins.  When the effect we believe is going to happen, does indeed happen, and proves to be good, we call that effect placebo (Latin: I shall please)

         In scientific studies placebos are used as controls, against which the active treatments are measured.  There are certain conditions that respond favorably to placebos and others that do not.  Conditions that primarily depend on feelings and have no specific physical signs such as depression, anxiety, fatigue, pain, headache, insomnia, etc. have a placebo response of about 30% or more.  In such cases, comparing the active treatment with the placebo may not reveal a large difference.  However, in conditions where measurable physical indicators are evident such as infections, broken bones, strokes, heart attacks hemorrhages, etc. the placebo response is extremely low.

         Our belief systems and our human natures predetermine our placebo responses.  If one believes that antibiotics help bronchitis, then taking an antibiotic may help one feel better in spite of the fact that acute bronchitis is a viral infection and antibiotics only kill bacteria.  If one believes that vitamin C helps colds, one tends to improve on vitamin C even though it has no antiviral effects.  If one believes in homeopathy, one tends to respond to homeopathic treatments even though they carry no scientific validity.  As a rule, self-limited diseases that heal naturally can respond very favorably to placebos.  However, severe diseases that worsen when untreated show a very poor placebo effect.  If one has a deadly but treatable cancer and believes that herbs are the best treatment for it, then one will most likely die of that cancer in spite of one’s strong belief in herbs.

         Studies show that belief can change brain chemistry, modify brain connections, activate selective brain regions, and influence treatment outcomes.  If an enthusiastic physician confident of success administers a treatment the patient would be more likely to respond than if the physician lacked enthusiasm and confidence.  Certain sham treatments work quite well if administered with confidence to gullible patients and billions of dollars are spent annually on such treatments all over the world.  Scientific treatments, which have been proven effective in controlled studies, may have enhanced, placebo effectiveness when administered in a way that inspires confidence.  Seasoned physicians know very well how to use the placebo effect to enhance the therapeutic benefits of their scientifically proven treatments.

         Just like negative beliefs can block the placebo effect, so can medicines and brain disorders.  The narcotic antagonist, Naloxone, can block the pain relieving effect of placebos while dementias can resist all kinds of placebo effects.  Informing depressed patients who, unknowingly, have done well on a placebo, that they are not taking the real treatment causes them to quickly relapse into depression.  Because researchers have become more interested in understanding the placebo effect, rather than just controlling for it, a program in placebo studies was recently established at the Harvard Medical School.

         A placebo, when presented as a muscle relaxant will cause muscle relaxation, when presented as a stimulant will increase heart rate and blood pressure, when presented as caffeine will cause arousal, and when presented as alcohol can cause feelings of intoxication.  Large pills can have greater placebo effects than small pills and colored capsules have a more powerful placebo effect than white pills.  A person describing how much a certain inert substance, such as a plastic bracelet worn around the wrist, has helped his arthritis can influence others to wear the same bracelet and realize the same benefit.  Many immune processes are influenced by the placebo effect such as asthma and eczema.  Similarly, side effects have been attributed to inert placebos in controlled trials as much as they have been to the active treatments.  Withdrawal symptoms have even occurred when inert placebos were abruptly discontinued.

         Placebos do not work for everyone.  Depending on the disease and cultural beliefs, estimates are that a third of humanity is susceptible to placebos and it is this third that keeps healers without scientifically valid, controlled studies in business.  However, this placebo effect tends to diminish with time and with the increasing severity of the disease being treated.

         It is not unethical to use the placebo effect to enhance scientifically validated treatments.  But it is unethical to knowingly prescribe placebos to unsuspecting, uninformed patients because that is a form of deception.