Tables show the use of antimicrobials in Japan between 2013 and 2017, based on the amount of sales. Overall use of antimicrobials in Japan in 2017 amounted to 13.8 DID (DDDs/1,000 inhabitants/day). A comparison with DID in major countries in 2015  shows that this was lower than France (35.7), South Korea (29.8), the U.S.A. (28.2), and Germany (18.2), but higher than Sweden (12.9) and the Netherlands (11.3). No major changes in the use of antimicrobials were observed between 2013 and 2016, but use in 2017 declined by 7.3% from the 2013 level.
Oral antimicrobial use in 2017 was 12.8 DID, accounting for 92.4% of all antimicrobials. Antimicrobials subject to a reduction target of 50% under Japan’s National Action Plan on AMR, namely oral macrolides (4.2 DID), oral cephalosporins (3.4 DID), and oral fluoroquinolones (2.6 DID) together accounted for 73.7% of all oral antimicrobials (the figure for oral cephalosporins is the total for first- (0.1 DID), second- (0.3 DID), and third-generation (3.1 DID) oral cephalosporins). While this trend has not changed since 2013, use of oral macrolides, oral cephalosporins, and oral fluoroquinolones fell by 13.5%, 12.2%, and 9.1% respectively over that period. On the other hand, use of parenteral antimicrobials increased by 9.3% between 2013 and 2017.
A survey of oral and parenteral antimicrobial use in terms of potency by weight from a One Health perspective showed no change in overall use. One of the main reasons for the discrepancy between this and the standardized figures expressed as DID is believed to be the effect of the increased parenteral use of ampicillin/sulbactam, which has a high-potency daily dosage and is used to treat aspiration pneumonia in elderly people. While factors such as the increasing number of elderly people make it difficult to reduce the use of parenteral antimicrobials in Japan, the effects of the National Action Plan on AMR are believed to be influencing the proper use of oral antimicrobials. Continued efforts to ascertain the extent of antimicrobial use are required.