Objective Children can be a difficult population in which to administer medicines and many parents or caregivers may be inexperienced in the administration of paediatric medicines. The aim of this study was to determine the variations in volumes of doses of reconstituted antibiotic suspension using two calibrated administrative devices. Setting Measurements were conducted in a Dispensing Laboratory in New Zealand, using locally available commercial, standardized measuring devices. Method A medicine dropper and a spill-proof measuring spoon were selected and a dose of 3 ml, to be given three times daily for five days (45 ml) was used for the purposes of this study. Doses were weighed and corresponding volumes were calculated using the average weight per ml. Results The doses measured using the medicine dropper were consistently smaller than the doses measured using the spill-proof measuring spoon. Conclusion The current method of financial subsidy for the provision of liquid antibiotics in New Zealand should be investigated. Pharmacists must ensure that an appropriate measure and sufficient quantity is provided for optimal duration of treatment. This study contributes to the relatively sparse information available on the administration of children's medicines. It will have relevance for countries where pharmacy practice is determined largely by administrative departments.