Background The paediatric population is a dynamic group, with major changes in pharmacokinetics and pharmacodynamics. Unfortunately, most medications commonly used in children do not have an approved labelling for use in these patients and are not available in appropriate formulations.

Purpose To analyse extemporaneous formulas compounded in a Pharmacy Department for pediatric patients during 2009.

Materials and methods Descriptive retrospective study of pediatric extemporaneous formulas made during 2009 in a 400-beds general hospital with 68 pediatric beds. Doctor's orders, compounding formula register book and standardised protocols were consulted in order to obtain the data. Each unit produced was considered as a formula.

Results 2158 pediatric extemporaneous formulas were made for 139 patients (50% girls), which corresponds to 8% of all compounded formulations developed. Patients' average age was 28 months. 29% of them were younger than 1 month, 25% between 1 and 5 months, 10% between 6 and 12 months, 20% between 1 and 5 years and 16% were older than 5 years. 76% of extemporaneous formulas were solid oral formulas, 18% liquid oral formulas, 5% were sterile parenteral preparations and only 1% were topical formulas. 36 different active ingredients were used. The most common formulas were redosed oral nutrition, followed by bosentan, omeprazole and methimazole capsules and liposomal amphotericin B preparations. 25% of the patients needed more than one different extemporaneous formula.

Conclusions Pharmaceutical compounding is essential to provide the appropriate doses or dosage forms that paediatric patients require. The compounding pharmacist is instrumental in assisting the medical staff with developing these new treatments and compounded formulations to treat these patients. It would be desirable that drug manufacturers could produce strengths and dosage forms appropriate for children.