Appropriateness of paediatric vitamin prescribing in Vietnamese outpatient settings: associated factors

Objective Vitamin supplementation is widely practised in paediatric populations. This study aims to describe and evaluate vitamin prescribing practices in paediatric outpatients. Design A cross-sectional study. Setting A tertiary referral paediatric hospital in Vietnam. Patients 400 paediatric outpatients prescribed vitamin supplements. Main outcome measures Prescribing patterns were analysed by vitamin type, age group, body mass index (BMI) category and International Classification of Diseases, 10th Revision (ICD-10)-coded diagnosis. Dosage and age appropriateness were assessed against international guidelines (American Academy of Pediatrics/National Institutes of Health Office of Dietary Supplements/U.S. National Academy of Medicine). Results Multivitamin complexes (41.3%) and vitamin B 1 (27.0%) accounted for the majority of prescriptions, predominantly in children aged 1–10 years and in association with respiratory disorders (60.3%). Although 74.2% of patients had normal BMI, this group received 63.3% of combined vitamin and dietary supplement prescriptions. Overall adherence was high, with 91.5% of prescriptions meeting recommended dosages and 98.8% being age-appropriate. In multivariable analysis, gastrointestinal disorders were associated with a higher likelihood of inappropriate dosing (adjusted OR 4.92, p=0.005), while no demographic factors remained significantly associated with age-inappropriate prescribing after adjustment. Conclusion Paediatric vitamin prescribing in Vietnamese outpatient settings showed high adherence to recommended dosage and age criteria. A proportion of prescriptions exhibited dosage deviations, particularly among multivitamin and combination products. Gastrointestinal disorders were associated with an increased likelihood of inappropriate dosing. To improve dosing accuracy in resource-limited settings, the integration of weight-adjusted dosing algorithms and electronic prescribing alerts may be considered. Further studies are needed to clarify contributing factors and optimise prescribing practices.