Enter drug name:
The ADRS Chart
Adverse drug reactions are reported to the FDA voluntarily through the MEDWATCH system by healthcare professionals, patients, or others.
In turn, the FDA puts these reports in the AERS (Adverse Event Reporting System) and makes them available on a quarterly basis. The reports are numerous and require substantial work to make them interpretable.
Upon an examination of the AERS database, an interesting pattern is emerging: When all quarterly reports are summarized as percent of total reports for the quarter (thus giving the
frequency of each reported term relative to the total number of reports), the quarterly charts are markedly similar as depicted in the chart below. We have plotted the first and second quarter of 2007 for illustration.
The adverse reactions are sorted according the second quarter percentages. The first quarter is then plotted by matching on the adverse reaction terms so that the two quarters can be compared on the same reactions.
What does this mean? Most of us are taking medication occasionally,
and sometimes exhibit adverse events. These events may or may not be related to a drug we are taking at the time. We are encouraged to report these events through the MEDWATCH system, and they become a part of the AERS database.
Most of these events are mild, for example, headache, nausea, constipation, etc, and may be related to causes other than a drug (food, stress, etc.)
These events (and many others) are the background events that will occur in any population. Then of course, there are those events that are most likely drug related, and they add to the totality of reported events.
When examining the ADRS chart, it becomes evident that the background relative frequency of adverse reactions remains stable as the two quarters are almost superimposable.
Now we can examine reactions associated with individual drugs by plotting them against the ADRS chart. Reactions that are relatively more frequent with certain drugs will stand out against the background of all reports for the quarter, as is evident
in the case study of
Cox-2 Inhibitors.
or
Fluroquinolones also seen below.
