All medicines licensed for use in the UK are strictly regulated to ensure they are as safe as possible.
The entire process of medicine development is controlled and monitoring continues after medicines become widely available.
In the UK, the Medicines and Healthcare products Regulatory Agency (MHRA) is the organisation that looks after the safety of prescribed medicines and other health devices and equipment. Its main job is to make sure that medicines and medical devices, from painkillers to pacemakers, work properly and are acceptably safe.
The MHRA works closely with the European regulator, the European Medicines Agency (EMA), which oversees the safety of medicines across Europe. In some cases, the EMA takes the lead in licensing medicines used in the UK.
Ensuring safety
No product is completely risk free, so the MHRA uses as much information as it can to ensure the benefits of medicines to patients justify any possible risks.
Both the MHRA and EMA routinely carry out inspections to check all parts of the medicine development process, from testing to manufacturing, are carried out in line with strict regulations.
The MHRA assesses the results of clinical trials to decide whether or not new medicines should be licensed for use. Clinical trials are research studies that carefully test the safety and effectiveness of medicines, using strict criteria.
No medicine or medical device can be used in the UK until the MHRA or EMA has given it a licence that sets out how it should be used and what health condition it should be used to treat. Read more about licensing medicines.
However, no medicine is completely risk free and medicines can affect different people in different ways. For example, depending on your age and sex and what other medicines you may be taking, a medicine might cause you to have a side effect that someone else who is taking the same medicine does not have.
Ultimately, you and your healthcare professional have to weigh up the pros and cons of each medicine when deciding on the most appropriate treatment.
Monitoring safety
The MHRA continues to monitor the safety of medicines once they are in wider use, by checking reports about any problems or defects and reviewing new scientific evidence on different medicines.
If any problems arise, the MHRA can take action to deal with it. This may mean alerting healthcare professionals about a potential issue with a medicine and withdrawing a medicine from the market if it becomes apparent that side effects outweigh the benefits.
For example, in July 2012, the EMA recommended some alterations to the licence for a medication called calcitonin, which increased calcium levels in the bones, so it was no longer used to treat osteoporosis. A review of the medicine found an increased risk of cancer after long-term use. Therefore, calcitonin is now only used for serious conditions, such as Paget’s disease, when the benefits outweigh the risks.