Objective: Similarity in drug appearance is one of the major environmental factors influencing dispensing errors, such as picking the wrong medication (picking error).  The purpose of this study is to verify if the index values of appearance similarity calculated objectively for multiple-specification drugs are the factors of picking error.
Methods: Four variables (number of total prescription, deviation of prescriptions between the specifications, sheet size, and color similarity of the sheet surface) were calculated.  The number of total prescription and deviation of prescriptions were extracted from the dispensing system.  Sheet size and color similarity were calculated, respectively, from the area ratio and by the Histogram Intersection method using the press through package (PTP) sheet image.  To evaluate the relationship between the picking error rate and these four variables, univariate and multivariate analyses were performed.
Results: The number of total prescription and the deviation of prescriptions were not significant factors.  In contrast, sheet size and color similarity significantly influenced the picking error rates.
Conclusion: Similarity in appearance between multiple-specification drugs is a risk factor of picking error.  When the multiple-specification pair has the same sheet size or high color similarity, one needs to be caution of picking error.  Further, in the pharmaceutical industry, to reduce the risk of dispensing errors, it is desirable to carry out the devise to enhance the identity of each specification.

Decreased adherence to medications among the elderly has become a problem in recent years. To overcome this problem, the dispensing of one-dose packages of medicines has been suggested. The purpose of this study was to survey elderly outpatients in a regional hospital at the Tokachi Development and Promotion Bureau and to analyze the factors that influence patients’ preference for a one-dose package medicine. The dispensation of one-dose package medication was observed in 20% of elderly outpatients. A correlation between the percentage of dispensed one-dose package medications and the number of agents was observed. Furthermore, dispensing rates of one-dose package medications increased with aging. Within the various departments analyzed, one-dose packaging rate was high in the Departments of Cardiology and Psychiatry. In this study, the correlation between residential municipalities of outpatients and one-dose package medications was examined. In the municipalities with a high rate of aged individuals and high average of household members, one-dose package medication rate was low. Multivariate logistic regression analysis confirmed these factors as significant. That one-dose packaging rates increased with the number of drugs and aging are consistent with the notion that one-dose package medications are designed to increase drug adherence among the elderly. Interestingly, one-dose package dispensing rate was low in areas with advanced aging. Because aging in Japan is expected to advance in the future, it is important to survey one-dose package dispensations.