Objective: The government has been promoting further contribution to home care by pharmacists since almost all homebound patients are prescribed more than one medicine. However, little information is available on the adverse drug reactions (ADRs) in home care setting. This study was conducted to describe the ADRs reported by pharmacists in home care and examine factors related to their reports.

Design: Questionnaire survey

Methods: We requested patient-visiting pharmacists at community pharmacies throughout Japan to answer questions about their patients. Main questions included patient characteristics, number of drugs taken, presence of ADRs and details, and pharmacists' workload related to home-visiting.

Results: Data on 5,447 patients were collected from 1,890 pharmacies. The percentage of patients in whom the visiting pharmacists found ADRs was 14.4%. ADRs reported in 10 or more cases covered 12 categories, accounting for 85.2% of all ADRs. The top five categories were: dizziness, grogginess, or lightheadedness; gastrointestinal disturbances; clinical test value abnormality; altered mentation; and cutaneous symptoms. In seven of the 12 ADR categories, central nervous system drugs such as sleeping pills, antianxiety drugs, and psychoneurosis drugs were in the top three suspected drugs. Additionally, patients' gender, residential situation, and the number of drugs taken were implied as factors related to ADRs.

Conclusion：Our study indicated that, while the percentage of ADR occurrences in home-visiting service in Japan was at the same level as outpatients in other countries, drugs for the central nervous system accounted for a higher percentage of suspected drugs. Further, occurrence of ADRs was associated with the use of more than 6 concomitant drugs. These results suggest that physicians and pharmacists need to collaborate in decreasing the number and dose of central nervous system drugs.