A Placebo is a substance that appears to be a medical intervention but it is not in reality. It does not contain any active substance and also does not have any effect on human health. Placebos are available as pills, injections, or any other type of fake treatment. Sham interventions like mock electrical stimulation or simulated surgical procedures, and acupuncture needles are also considered as placebos. And among all these injections are seen to be more effective than the pills and sham surgery is the most powerful one.

Placebos make an individual feel better but do not have the ability to cure. These work on symptoms modulated by the brain like pain, stress related insomnia, fatigue, irritable bowel system, nausea etc and produce measurable physiological changes such as increased heart rate. Interventions of placebo vary in strength depending upon different factors. For example, two tablets may work better than one or capsules showing stronger effects than the tablets etc.

Types of Placebos:

• Pure or inactive : Sugar pills or saline injections
• Impure or active placebos: vitamins or antibiotics for viral infection (prescribed by the clinician even though the patient doesn’t need it).

Trials that include placebos can be single blind or double blind.

• Single Blind: In this the participant does not know they are getting the investigational treatment or the placebo. This is mainly to reduce placebo effect
• Double Blind: Both the researchers and the participants are unaware that they are provided with the investigational drug or the placebo. This reduces biasness in the study.

Most of the placebo involved studies are double blinded.

Placebos in clinical practice

Placebos can satisfy patient’s demand for treatment without exposing them to adverse effects and also makes them feel better. This is the reason why clinician prescribe placebo (rarely) to their patient having a mild, self limited disorder for which no active drug is present or indicated (eg, tiredness).

Reaction to placebo

People have different reaction to different placebos and everyone even does not respond to placebos. Predicting who will respond to a placebo is also not possible. Some people report beneficial effects while some other people report bad effects. Though the correlations between the characteristics of personality and the response to the placebos are theorized but they are not established well.

Response to placebos are also depended on the beliefs or thinking of people. Branded and expensive tablets are better painkiller than the cheap and generic one or two placebos are better than one, this is possibly because patients expect it.

Why placebo is important in clinical trials?

Nowadays placebos are often used in clinical trials to help clinical researchers to discover and make them understand the effectiveness of physiological and psychological effects of new medications or treatment. Placebo plays a vital role in getting new treatments or medications to the people.

Previously in clinical trials, the capabilities of a new medication were compared against a group of participants who didn’t take any medication. But on discovering that an empty tablet has the ability to produce a placebo effect, it is considered very important to have an additional third group that takes placebo. At present, in clinical trials, one group of participants is given the tested drug while another group is given a placebo. Placebos help the researchers to compare the results from the placebo and the results from the actual drugs. This lets them know whether the new medication is effective and whether any improvement is seen or not.

A medicine is approved, marketed, sold or prescribed only if it produces a greater effect than the placebo.