Paediatric prescribing & vitamin K
also: weight-based dosing · vitamin K newborn · paracetamol child · avoid aspirin
Overview
The cross-cutting safety rules of prescribing for children — weight-based dosing, age contraindications, and routine newborn vitamin K.
Mechanism
Children are not small adults: dose by weight (mg/kg, capped at the adult dose) and account for immature hepatic/renal handling. Newborn IM vitamin K corrects the physiological deficiency of vitamin-K-dependent clotting factors → prevents vitamin K deficiency bleeding (haemorrhagic disease of the newborn).
Indications
- Safe paediatric prescribing
- Routine newborn prophylaxis (vitamin K)
The agents
IM at birth (or oral course)
Prevents VKDB; IM is most reliable.
weight-based
Ibuprofen avoided in dehydration/varicella caution.
Adverse effects
Always check mg/kg and the adult cap.
Cautions & contraindications
Reye syndrome (except Kawasaki/specific indications).
Teeth staining / bone.
Variable CYP2D6 metabolism → respiratory depression.
Cartilage/tendon (relative).
Interactions
- As per individual drugs
Monitoring & kinetics
Weight at each prescription; recalculate as the child grows
Weight-based mg/kg dosing, capped at the adult dose.
Source: BNF for Children — Prescribing in children