Single-center survey of prescription trends and appropriate use plans for macrolide antimicrobials

Macrolides (MCs) are broad-spectrum antimicrobials with activity against many microorganisms. They are widely used, and the development of MC-resistant bacteria is a serious problem in Japan. It is therefore necessary to clarify the purpose and duration of administration, with the aim of promoting appropriate use.

Patients of all ages, for whom oral MCs were prescribed between 2016 and 2020 were included. They were divided into four groups based on the number of days per prescription. In the long-term treatment group, patients treated with MCs for ≥1000 days were specifically investigated for the purpose of treatment.

Macrolide prescriptions increased from 2019 to 2020. Most patients received ≥28 days of treatment based on one prescription. During the study period, 1212 patients (28.6%) received a total of ≥50 days and 152 patients (3.6%) received a total of ≥1000 days of treatment. Approximately a third of long-term administrations were for nontuberculous mycobacterial infections (NTMs), and 18.3% of patients with NTMs were treated with MCs alone. In addition, many MCs were administered for their anti-inflammatory effects on neutrophils.

Owing to their pleiotropic effects, MCs may also be administered for the treatment of noninfectious diseases. In general, the long-term administration of antimicrobials contradicts the strategy for the suppression of resistant bacteria. It is thus important to understand the actual clinical utility of MCs and the purpose and duration of administration. In addition, strategies for the appropriate use of MCs are required for each medical institution.