title: Off-label use of antimicrobials in neonates in a tertiary children's hospital.
abstract: OBJECTIVE
  Off-label (OL) use of drugs for hospitalized children is very common. OL use occurs especially in the youngest patients, neonates. This study focused on the OL use of antimicrobials in neonates. To our knowledge, only few studies have focused on the prevalence of OL use of antimicrobials in neonates.
  
  
  METHODS
  We investigated the OL use of antimicrobials in neonates in a tertiary children's hospital. First, we investigated what were the most consumed OL antimicrobials in defined daily doses according to hospital's registry data from neonatal intensive care unit (NICU) during 2009-2014. Second, we conducted a targeted retrospective study of premature neonates (400-2000 g) with blood culture-positive infections and receiving antimicrobial therapy between 2005 and 2014 (N = 282). The data were obtained from the electronic patient records and from the hospital's electronic infection registry. Statistical analysis was conducted by using a univariate logistic regression model fitted for OL usage.
  
  
  RESULTS
  In NICU, 35% (7/20) of antimicrobials used were OL. Eighteen percent (51/282) of premature neonates with blood culture-positive infections received at least one antimicrobial OL. The most commonly used OL antimicrobials in neonates were meropenem 88% (45/51), rifampicin 18% (9/51), and ciprofloxacin 8% (4/51). The odds for OL use were significantly higher the smaller the neonate birth weight was. An increase in birth weight was found to statistically significantly decrease the probability of OL usage (odds ratio = 0.85 for 100 g increase in birth weight, p value <0.001).
  
  
  CONCLUSIONS
  More studies in neonates on especially dosing and pharmacokinetics of antimicrobials are urgently needed.
authors.affiliation: Children's Hospital, Helsinki University Hospital, Stenbäckinkatu 11, 00029 HUS, Helsinki, PL 281, Finland. niina.laine@helsinki.fi.|Department of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Viikinkaari 9, 00014, Helsinki, Finland. niina.laine@helsinki.fi.
authors.forename: Niina
authors.initials: N
authors.lastname: Laine
authors.affiliation: Formulation and Industrial Pharmacy Unit, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.|Current address: Finnish Medicines Agency (FIMEA), P.O. Box 55, 00034, Helsinki, Finland.
authors.forename: Ann Marie
authors.initials: AM
authors.lastname: Kaukonen
authors.affiliation: Children's Hospital, Helsinki University Hospital, Stenbäckinkatu 11, 00029 HUS, Helsinki, PL 281, Finland.|Poison Information Centre, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Kalle
authors.initials: K
authors.lastname: Hoppu
authors.affiliation: Department of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Viikinkaari 9, 00014, Helsinki, Finland.
authors.forename: Marja
authors.initials: M
authors.lastname: Airaksinen
authors.affiliation: Children's Hospital, Helsinki University Hospital, Stenbäckinkatu 11, 00029 HUS, Helsinki, PL 281, Finland.
authors.forename: Harri
authors.initials: H
authors.lastname: Saxen
mesh_terms: D000890:Anti-Infective Agents / Q000627:therapeutic use*; D006776:Hospitals, Pediatric; D006801:Humans; D007231:Infant, Newborn; D062606:Tertiary Care Centers
chemical_list: D000890:Anti-Infective Agents
keywords: Antimicrobial; Children; Neonatal intensive care unit (NICU); Off-label use; Paediatric; Premature neonate