Adverse drug reactions (ADRs) are a well recognized
public health problem worldwide and
a major cause of death and hospitalization in
developed countries.[1] In fact, rare and long-term
ADRs are difficult to detect during the drug
development stage. Only when the drugs begin to
be used by a large population after marketing
authorization is it possible to detect new ADRs
not previously identified during clinical trials.
In reality, the safety of a new drug cannot be
established until it has been on the market for
several years.[2] As such, it is essential to keep reactions
to drugs under close surveillance, especially
after marketing, through a pharmacovigilance
system.