Most women use medication during pregnancy. The disposition of drugs may be altered due to changes in pregnant women's bodies. This may call for pregnancy-adjusted doses for certain medications. However, in the face of scarce evidence, such doses are generally lacking, potentially contributing to an increased risk of treatment failure or toxicity in pregnant women and their unborn children. By integrating physiological and/or population data, pharmacokinetic models can be used to determine appropriate medication dosages among pregnant women and their unborn children, as well as other patient groups for which evidence-based doses may be lacking such as children, elderly or obese patients. In order to translate model predictions into clinically usable doses, a number of conditions must be met, including careful model validation, an assessment of evidence from pharmacokinetic modelling alongside available clinical studies by multidisciplinary experts, as well as transparent communication towards end-users on the considerations for determining appropriate medication doses.