Abstract
Many commercially available medications are often unapproved or unavailable in suitable dosage forms for specific patient populations, particularly infants and children. This necessitates the use of extemporaneously compounded formulations to deliver individualized doses based on body weight or body surface area, and when a medication is unavailable at an appropriate concentration or contains excipients potentially unsafe for certain patients. Extemporaneous compounding is required for oral liquids when patients are unable to swallow tablets or capsules. It is also needed for topical preparations and sterile dosage forms when commercial products are unavailable. Across regions, practices follow national pharmacopeial standards for both sterile and non-sterile compounding. Stability factors influencing the safety and efficacy of compounded formulations must be carefully considered when assigning appropriate beyond-use dates. While stability information is available for some medications in monographs, peer-reviewed literature, prescribing information, and investigator's brochures, such data is often lacking for many compounded preparations. Emerging extemporaneous formulations-such as orodispersible films, nanoparticle systems, and 3D-printed compounds-offer potential advantages over traditional compounded formulations but present unique challenges to widespread implementation. Despite the justified clinical need for extemporaneous compounding, significant barriers remain, including limited access to medications, insufficient compounding expertise or resources, gaps in pharmacokinetic and safety data, and regulatory constraints. This review critically appraises the current state of extemporaneous compounding-drawing primarily on the United States of America frameworks-and highlights its continued necessity, associated challenges, and pragmatic solutions for advancing personalized pharmacotherapy across pediatric age groups worldwide.