A–Z of prescribing for children

The neonatal period refers to the first 28 days of life for a term infant. Prescribing for neonates differs from that for older children and adults due to differences in anatomy and physiology, impacting drug pharmacokinetics (Ku and Smith, 2015). As a result, drug dosages need to be modified constantly due to the infant's weight increase, and the gradual maturation of metabolic pathways (Ruggiero et al, 2019).

Absorption can vary greatly in neonates; compared to children, where the oral route is preferred, it may not be an option for a neonate who is seriously ill or cannot swallow, and taste is also an important factor (Linakis et al, 2016). Gastric emptying times are delayed, alongside a reduced gastrointestinal motility, resulting in an increased length of time for peak concentrations of the drug (Anderson, 2022). Volume and gastric pH also differs, with a drop in pH shortly after birth, and then a rise, with a return to ‘adult’ levels around the age of 2 years (Linakis et al, 2016).