Analysis of spontaneous inquiries about suspected adverse drug reactions posted by the general public on the electronic Japanese bulletin board “Yahoo! Japan Chiebukuro”

PURPOSE Spontaneous inquiries about the development of adverse drug reactions (ADRs) to medicines can be extracted based on the questions posted by the general public on the electronic Japanese bulletin board "Yahoo! Japan Chiebukuro". Our aim was to clarify the characteristics related to people's descriptions of suspected ADRs and determine the reasons for submitting a spontaneous inquiry. METHODS Fifty brand names of medicines used for inquiry extraction were chosen by selecting 35 pharmaceutical products, based on the generic names that had the highest sales in Japan. Questions containing both the brand name of one of these medicines and the term "Fukusayō" (ADR in Japanese) that were posted from July 2004 to June 2009 were extracted from the site. RESULTS Among 1,419 questions extracted, 614 questions had at least one identifiable brand name of a suspected medicine, an ADR description, and the extent to which the ADR appeared to be caused by the suspected medicine(s). Among these 614 questions, 589 described in detail the symptoms/signs that the inquirers themselves or their families had experienced as ADRs. The highest number of questions was found for Paxil (525). Posts asking whether the symptoms being experienced were due to an ADR accounted for the highest number of questions. In most cases, the inquirer suspected that a single medicine led to an ADR and was seeking advice from others taking the same medicine. CONCLUSION Our examination of spontaneous inquiries showed that people have sufficient knowledge to adequately report potential ADRs in terms of their symptoms, suspected medicines, and the disease for which the medicine was used. However, they often did not describe the start time when the ADR appeared or when the suspected medicine was started.