The Factors Contributing to Expenditures on Over-the-Counter Drugs in South Korea

To determine the factors contributing to the use of over-the-counter (OTC) drugs and to examine the relationship between the purchase of OTC drugs and the utilization of health care services in South Korea.

This study used data from the 2008 Korea Health Panel Survey. The respondents were classified according to the purpose of the OTC drug use. The first group (n = 364) included respondents who had purchased OTC drugs for self-medication, and the second group (n = 955) included respondents who had taken OTC drugs for nutrition for more than 3 months. Logistic regression analyses were conducted to identify the factors contributing to the purchase of OTC drugs.

The self-medication group was more likely to be older and to have a chronic disease. In addition, the purchase of OTC drugs was related to the utilization of other health care services. The more outpatient services at clinics were used, the more the respondents tended to purchase OTC drugs for self-medication and nutrition. As hospital outpatient visits increased, however, the purchase of OTC drugs for self-medication decreased and the purchase of OTC drugs for nutrition increased.

This study shows that age and chronic disease are the major factors related to using OTC drugs for self-medication for long-term periods. Furthermore, this study suggests that the use of outpatient services is one of the factors associated with purchasing OTC drugs. Considering the potential adverse effects of OTC drugs, communication between physicians and patients should be encouraged at outpatient visits.