European Surveillance of Antimicrobial Consumption (ESAC): outpatient quinolone use in Europe

Background: Data on outpatient quinolone use in Europe were collected from 25 countries within the ESAC project, funded by DG SANCO of the European Commission, using the WHO ATC/DDD methodology. Methods: For the period 1997-2003, data on outpatient use of systemic quinolones aggregated at the level of the active substance were collected and expressed in DDD (WHO, version 2004) per 1000 inhabitants per day (DID). Because a new DDD for levofloxacin was published in the ATC 2004 index (0.5 g instead of 0.25 g) all data were recalculated accordingly. Quinolone use was analysed in detail, using a classification into three generations based on their pharmacokinetic and in vitro potency profiles, which determines the area of clinical use. Results: Total outpatient quinolone use in 2003 varied by a factor of 12 between the country with the highest (3.10 DID in Portugal) and lowest (0.25 DID in Denmark) quinolone use. The second-generation quinolones represented more than 50% of the quinolone use (mainly ciprofloxacin) except for Croatia, where the first-generation was used most (mainly norfloxacin). In 22 countries, the use of second and/or third-generation quinolones increased at the expense of the use of first-generation quinolones. The new so-called respiratory quinolones (levofloxacin and moxifloxacin) represented more than 10% of quinolone use in 12 countries, with extreme seasonal variation in all these countries except for one. Conclusion: There has been a substantial change in the use pattern of quinolones between 1997 and 2003, since the introduction of quinolones that are effective for the treatment of respiratory tract infections. These quinolones are not the first-line antibiotics for this indication and therefore quinolone use should in general still be limited and not show substantial seasonal variation.