
Post Marketing Surveillance (PMS) Post Marketing Surveillance (PMS), also known as post
marketing monitoring or pharmacovigilance, is the process of monitoring the safety, effectiveness,
and quality of a drug or medical product after it has been released into the market. It is an essential
part of the drug regulatory system that ensures medicines remain safe when used by the general
population. After a drug completes clinical trials and is approved, it is released for public use.
However, clinical trials are conducted on a limited number of patients under controlled conditions.
Therefore, rare side effects or long-term adverse reactions may not be detected during trials. PMS
helps to identify such hidden risks when the drug is used by a larger and more diverse population.
The main objectives of PMS include detecting adverse drug reactions (ADRs), ensuring the
continued safety and efficacy of medicines, improving public health, and providing feedback for
regulatory decisions. It also helps in updating drug labels, changing dosage recommendations, or
even withdrawing harmful drugs from the market if necessary. There are several methods used in
post marketing surveillance. These include spontaneous reporting systems where healthcare
professionals report adverse reactions, cohort event monitoring, case-control studies, prescription
event monitoring, and patient registries. Regulatory authorities such as drug agencies collect and
analyze this data to make informed decisions. The importance of PMS is very high in public health.
It ensures patient safety, builds trust in healthcare systems, and supports rational use of medicines.
It also plays a key role in identifying drug interactions, rare side effects, and issues related to
long-term drug use. Without PMS, many harmful effects of medicines might remain unknown until
serious damage occurs. Despite its benefits, PMS also has some limitations. Underreporting of
adverse reactions is a major problem. Lack of awareness among healthcare professionals and
patients can reduce reporting efficiency. Sometimes, data collected may be incomplete or biased,
which can affect decision-making. In conclusion, Post Marketing Surveillance is a vital component
of the pharmaceutical system. It bridges the gap between clinical trials and real-world drug use. By
continuously monitoring medicines after approval, PMS ensures safer healthcare and improves the
overall quality of treatment for patients.