South Korea has a universal National Health Insurance (NHI) system, which has provided greater access for citizens to basic and cutting-edge medical care since the system was introduced in 1989 (Table 1) [192021]. It covers both medical and pharmacy benefits for the entire population. Under the scheme, all office-based physicians dispense drugs in their clinics; the NHI system then reimburses them for the dispensed drugs at pre-determined prices for each drug, thus allowing the physicians to profit on any mark-up over drug purchase costs.

After the introduction of the NHI system, healthcare expenditure continued to rise, and drug spending as a proportion of total healthcare expenditures increased to 26.3% in 2000 [19]. Antibiotics are one of the top drug classes by expenditure. Antibiotic costs accounted for 33.1% of the total pharmaceutical expenditure in 1997 [22]. In the same year, antibiotic use was 33.2 defined daily doses (DDD) per 1,000 inhabitants per day, based on IMS data (IMS Health Korea, Seoul, South Korea), compared with the Organisation for Economic Cooperation and Development (OECD) average of 21.3 [22].

Eventually, in July 2000, the South Korean government implemented a new policy that prohibited physicians from dispensing drugs, and pharmacists from prescribing them. The reform aimed to fundamentally change the inefficient pattern of provision and consumption of pharmaceuticals, to reduce the resultant overuse and misuse of drugs including antibiotics, and to contain pharmaceutical expenditure [2324].

Concerns arose early on over the possibility of misuse and abuse of antibiotics, injections and high-priced prescriptions, and the health authorities felt it necessary to evaluate the medicines that account for a large proportion of the supply of medications [20]. In July 2000, the National Health Insurance Act was amended to introduce functions for quality assessment of NHI benefit/coverage. The act defines the adequacy assessment service as the duty of the Health Insurance Review and Assessment Service (HIRA), an agency charged with assessing reimbursement of claims under the NHI system. Since then the HIRA has been in control of nationwide quality assessment and has introduced government-driven programs of quality assessment of antibiotic use, as shown in Table 2 [2021].

Initially three categories of outpatient medications prescribed by physicians, comprising antibiotics, injections, and medication costs per day, were evaluated by the HIRA, starting in 2001. The assessment subjects were determined according to the primary diseases (Korean Outpatient Group and Korean Classification of Diseases, Middle Classification) indicated in insurance claims [20]. The indicators for the quality assessment were proportion of antibiotic prescriptions for all diseases and acute URTIs, although national guidelines for the management of URTIs had not been developed. The prescription patterns of all healthcare facilities were analyzed, and feedback about the results was provided to every healthcare facility in an effort to reduce misuse and to promote proper use by strengthening each healthcare facility's autonomy in the use of medications [20]. Antibiotic use for acute otitis media in infants and children since 2012 has been reviewed [21].

Since 2007, the HIRA has publicly reported the results of the quality assessments to help consumers chose hospitals that offer high-quality medical services [25]. The quality indicator results for individual hospitals are posted on the HIRA website.

In the late 1990s, the prescription of antibiotics for diseases that did not need antibiotics was common in outpatient clinics in South Korea. For example, a study of insurance claims in 1994 showed that primary care physicians prescribed antibiotics in 90% or more of adults and children with the common cold and acute bronchitis [11]. The number of antibiotics prescribed was 1.6 per person. In 1999, 51.5% of family physicians prescribed antibiotics for adults and children with the common cold [12].

Since the implementation of the new policies, however, the proportion of antibiotics prescribed for acute URTIs has dramatically decreased, as shown in Fig. 1 [111221]. Overall, the proportion of antibiotics prescribed for patients with acute URTI in primary healthcare facilities decreased from 72.9% in 2002 to 42.7% in 2013. As the percentage of antibiotics prescribed for the treatment of acute URTIs decreased, the overall proportion of antibiotics prescribed per total prescription for outpatients also decreased, from 41.6% in 2002 to 21.5% in 2013 (Fig. 2) [2627].

The perceptions of physicians and pharmacists about antibiotic prescription for acute URTIs have also changed over the past two decades (Fig. 3) [28293031323334]. Studies using clinical scenarios involving the common cold or acute bronchitis showed that physicians’ responses in favor of antibiotic prescription in acute URTIs fell from 75.0% in 1991 to 54.7% in 2003 and to 27.2% in 2010 although the clinical cases and study subjects differed between the studies (Fig. 3A) [282930].

Studies using standardized patients with the common cold also confirmed that primary care physicians have prescribed antibiotics less frequently since the separation of drug prescribing and dispensing (Fig. 3B) [31323334]. The decline in antibiotic prescription was more evident after introduction of the public reporting policy.

In short, the separation of drug prescribing and dispensing was the single largest factor to alter overall antibiotic use. The overall proportion of antibiotic prescriptions dropped abruptly after the separation of drug prescribing and dispensing (Fig. 4) [353637]. After implementation of the separation policy, antibiotic use decreased from 28.8 DDD per 1000 inhabitants per day in 1998 to 20.1 in 2002, according to IMS data [35]. The subsequent implementation of public reporting of antibiotic use also led to a modest decrease in antibiotic use for a short period, but it soon started to rise again [37]. According to NHI reimbursement claims data from 2005 to 2009, overall consumption of insurance-covered antibiotics for outpatients decreased from 22.3 DDD per 1,000 inhabitants per day in 2005 to 19.1 in 2007 but then increased to 22.8 in 2009 while change in antibiotic consumption for inpatients was insignificant between 2.3 and 2.5 DDD per 1,000 inhabitants per day during the same period [37]. Most recent data reported to the OECD Health Statistics, including consumption of both insurance-covered and non-insurance-covered antibiotics, have revealed a slowly increasing trend of antibiotic consumption from 26.9 DDD per 1000 inhabitants per day in 2008 to 28.4 in 2012, compared with 20.3 DDD per 1000 inhabitants per day for the OECD mean [38].

Following the reduction of antibiotic use in the treatment of acute URTIs in outpatient services in the last decade, there has also been a fall in the estimated cost of antibiotics used in outpatient services. The estimated reduction in the cost of antibiotics for acute URTIs was 60.8 million US dollars from 2004 to 2007, with a mean of 15.2 million US dollars per year [39].

Little is known about the effect of antibiotic control in the treatment of acute URTIs on antibiotic resistance in South Korea. Rates of beta-lactam and macrolide resistance in Streptococcus pneumoniae have been very high [40]. The rates of penicillin-resistant S. pneumoniae, defined as minimum inhibitory concentrations for penicillin G ≥0.12 mg/L, have been slowly increasing from 0% in 1981 to 77.1% in 2009 (Fig. 5) [4041424344454647]. Resistance to erythromycin also increased from 39.0% to 84.3% over the same period. Meanwhile, the 23-valent pneumococcal polysaccharide vaccine (PPV) was introduced in South Korea in 1991, the pneumococcal conjugate vaccine 7 (PCV7) in 2003, and both PCV10 and PCV13 in 2010 [48]. Because PPV and PCV were only recently included in the national immunization program for older adults (2013) and children (2014), respectively [49], and because of the low rates of PPV vaccination (<6%) [50], it is too early to evaluate the impact of pneumococcal vaccination on pneumococcal resistance.