Background Licensed medicines for children are rare. Pharmacy preparation plays a crucial role in this vulnerable patient group but its quality must be assessed carefully. Our hospital pharmacy prepares various capsules for children by crushing and diluting licensed products. For the requested low concentrations, high and sometimes serial dilutions are necessary. The authors follow good pharmacy practice and use uniformity of mass as our routine quality control.

Purpose This study was conducted to assess the quality of our children's capsules and therefore contribute to patient safety. Specifically, the authors investigated the feasibility and quality of our dilutions and to see if conformity of mass was sufficient as a single routine quality check.

Materials and methods Simulating standard concentrations, procedures and quantities, sample NaCl capsules were produced by each member of the production team.

The capsules were analysed for uniformity of mass and content according to PH.EUR.6.

Means, minimum and maximum values (in % of the labelled concentration) were identified.

Results 22 samples, each containing 50 capsules of either 0.1 mg or 1 mg were produced. All samples met the PH. EUR. requirements for uniformity of mass. As for content: of the 0.1 mg group (n=11), 2 (18%) met PH. EUR. criteria, 2 (18%) required further analysis and 7 (64%) failed. The average content was 83.5% (53.1%-105.5%) of the labelled concentration. In the 1 mg group (N=11), 3 (27%) conformed to the PH. EUR. criteria, 3 (27%) were eligible for further analysis and 5 (46%) did not meet the criteria. The average content was 86.1% (78.1%–95.3%) of the labelled concentration.

Conclusions Our study indicates that a routine check of conformity of mass is not sufficient for quality assurance of our preparations. It also showed that the dilutions do not seem to result in acceptable concentration ranges in the capsules. A re-evaluation of the products and our production methods is planned.