Understanding a web report

When you view a web report of suspected side effects (also known as suspected adverse drug reactions) for a medicine or active substance, it is important to understand how the web report fits into the overall safety profile of a medicine.

Here is a list of important points to consider when viewing a web report:

  • For a medicine to be authorised for use, its benefits should outweigh any associated risks of side effects. At the time of authorisation of a medicine, the benefit-risk balance has been assessed and the benefits judged to outweigh the risks. All the information available on this website relates to medicines that have been assessed in this way and authorised for use in the European Economic Area (EEA).
  • The information on this website relates to suspected side effects, in other words, effects that have been observed following administration of, or treatment with, a medicine. However, these suspected side effects may not be related to or caused by the medicine.
  • All medicines can cause side effects, and it is important to note that most people take medicines without suffering any side effects.
  • Before a medicine is marketed, information on its safety and efficacy is based on use of the medicine in clinical trials. However, clinical trials may not be able to detect all side effects, as they involve limited numbers of patients. Also, some side effects may take a long time to develop, and only occur after the clinical trial is finished. Often (but not always), people taking part in clinical trials are healthy or do not have other diseases or do not normally take other medicines. This is not the situation when the medicine is used in 'real life'. Continuous monitoring after the clinical trial is therefore essential, to maintain a comprehensive safety and effectiveness profile of the medicine. All medicines authorised for use in the EEA are continuously monitored.
  • A case can be reported on the basis of a suspicion that the side effect is associated with the medicine. It does not necessarily mean that any link between the medicine and the side effect has been established; the side effect may have occurred due to other factors, for example the disease for which the medicine is being taken or an interaction between two or more of the patient's medicines.
  • Any individual case report should be seen in the context of all available data on the medicine. Apart from the spontaneous reports arising from the use of the medicine worldwide, there may also be reports from clinical trials, other studies and the scientific literature. Only the assessment of all available data allows for robust conclusions on the benefits and risks of a medicine to be drawn.
  • The information on this website cannot be used to determine the likelihood of experiencing a side effect. Other information, such as how many people take the medicine and how long it has been on the market, need to be considered.
  • The information is only part of the information used by the European Medicines Agency and national medicines regulatory authorities to monitor the benefits and risks of a medicine once it is authorised. Other types of information include post-authorisation safety studies, clinical-trial data and new toxicology data.
  • For more comprehensive information about the risks or possible side effects of a medicine, always refer to the summary of product characteristics and the patient information leaflet (included with the medicine). Healthcare professionals such as doctors and pharmacists can also provide this information.

Any concerns related to a medicine should always be discussed with a healthcare professional. The Agency cannot advise individual patients on their treatment or condition.