Off-label Use of Oral Fluoroquinolone Antibiotics in Outpatient Settings in the United States, 2006 to 2012

Purpose: The aim of this study was to evaluate the practice pattern of off-label use of fluoroquinolones (FQs) in ambulatory settings and to identify the related risk factors.

Methods: The National Ambulatory Medical Care Surveys from 2006 through 2012 was used to identify subjects who received FQ off-label prescriptions. We defined off-label use as the use of FQs for indications other than those in the FDA-approved drug label. Descriptive statistics were calculated by using a series of weighted chi-squared statistics. Multivariate logistic regression was conducted to identify factors associated with off-label FQ drug use.

Results: There were 93 million ambulatory visits in which an FQ was prescribed, and 53.16% of these visits involved the prescribing of FQs in an off-label manner. The percentage of off-label prescriptions was the highest among individuals ≥80 years old (61.6%) and male patients (60.9%). The FQ drug prescribed most for an off-label indication in our study was ciprofloxacin (29.5% of the total visits). The multivariate analysis showed that age of ≥80 years and male patient was significantly associated with off-label use of FQs (adjusted odds ratio (OR) 3.66, 1.72-7.80 and OR 3.26, 2.32-4.56, respectively). Medicaid or private insurance versus Medicare were associated with significantly higher off-label prescribing of FQs (OR 2.53, 1.28-5.01 and 1.77, 1.03-3.03, respectively).

Conclusion: The percentage of visits involving off-label FQs in US ambulatory settings is substantial. Efforts are needed consolidate and evaluate what high-quality scientific evidence is available and what is needed to support the safety and effectiveness of such off-label uses. Copyright © 2016 John Wiley & Sons, Ltd.