A placebo can be defined as an inert pill, injection, or other sham intervention that masks as
an active intervention in an effort to maintain blinding of treatment assignment. It is termed
the “sugar pill” and does not contain an active ingredient for treating the underlying disease
or syndrome but is used in clinical trials as a control to account for the natural history of
disease and for psychological effects. One disadvantage to the use of placebos is that sometimes they can be costly to obtain