Guidelines for ATC classification and DDD assignment ... - WHOCC

- Liquid preparations for inhalation:1 UD equals 1 ml of the preparation.- Liquid preparations for inhalation in single dose units (unit dose):1 UD equals 1 unit dose inhal.sol- Enemas:1 UD equals 1 enema.- Plaster for transdermal application:1 UD equals 1 plaster.- Vaginal cream:1 UD equals 1 dose, 1 application.Route of administrationThe route of administration is indicated by the following codes:Inhal = Inhalation R = RectalN = Nasal SL = Sublingual/buccal/oromucosalO = Oral TD = TransdermalP = Parenteral V = VaginalC. Pediatric DDDDDDs are normally assigned based on use in adults (see page 22).For medicinal products approved for use in children, the dose recommendationswill differ based on age and body weight. Many medicinal products used inchildren are not even approved for such use, and documentation regarding doseregimens is not available.Thus the WHO International Working Group for Drug Statistics Methodology hasconcluded that pediatric DDDs are impossible to assign and problems related todrug utilization research in children cannot be solved by such means.Estimating prevalence of drug use in children is not possible by using crude salesdata presented in DDDs. Prescribed daily dosages and indications in a pediatricpopulation should be used if available and compared with the DDD values. If thepediatric subgroup is difficult to identify, the general DDD should be used as ameasuring tool for overall comparisons.28