Placebo, Is used to describe a substance given in clinical trial that does not contain the drug.
Explanation:
Clinical trials are done to evaluate the effectiveness of a drug in treating a particular medical symptom or disease.
In such case a placebo is used as a control in the experiment.
A placebo contains all the components as the medicine except for the drug that is being tested.
A placebo is given to one group of patients having the symptoms for which the drug is tested while another group of patients with same symptoms are given the drug.
If the group that was given the drug show symptoms of cure while the group that was given placebo does not show changes. Then the drug is said to be effective.
