Background: Defined daily dose (DDD) is a unit that gives an estimate of drug utilization. The DDDs that are developed today are only based on adult’s drug use. That means that the DDDs for adults may not necessarily apply to children. 

Aim: To calculate recommended daily dose for boys and girls in different ages and compare it with DDD for adults for paracetamol, phenoxymethylpenicillin, desloratadine and melatonin.  

Methods: This descriptive cross-sectional study was conducted September-October 2021. Boys and girls in ages 1, 5, 12 and 16 years were included. Data was retrieved from FASS.se, tillväxtkurvor.se and WHO Collaborating Centre for Drug Statistics Methodology. 

Results: The children’s daily doses are lower than DDD for adults for paracetamol for all ages, phenoxymethylpenicillin for ages 1, 5 and 12 and desloratadine for ages 1 and 5. The daily doses of phenoxymethylpenicillin aged 16 are higher than DDD for adults. Daily doses for melatonin and desloratadine age 12 and 16 were the same as DDD for adults. Paracetamol and phenoxymethylpenicillin have variations in the daily doses for the children. Girls in all ages except from 12 years and the youngest children had lowers doses. Desloratadine ages 1 and 5 had the same dose and ages 12 and 16 had the same dose. For melatonin the children received the same doses. 

Conclusion: The calculated recommended daily doses for children are to some extent in line with WHO DDDs. In order to use WHO DDDs in children, it is important to have knowledge of which drugs and ages they can be applied for.