Can children swallow tablets? Outcome data from a feasibility study to assess the acceptability of different-sized placebo tablets in children (creating acceptable tablets (CAT)).

OBJECTIVE: Feasibility study to investigate the acceptability of different-sized placebo tablets in children aged 4-12 years. DESIGN AND SETTING: Clinical Research Facilities, inpatient wards and outpatient clinics within a Regional Paediatric Hospital and/or District General Hospital. Healthy children and National Health Service (NHS) patients were asked to swallow three placebo tablets: 6 mm, 8 mm and 10 mm, smallest to largest. The researcher observed children's facial expressions and behaviours on swallowing and measured the volume of water consumed. Participants completed a questionnaire about the overall acceptability; including swallowability, taste and volume of water consumed. For analysis, participants were stratified by age: 4-8 years and 9-12 years. RESULTS: The feasibility study led to an estimated recruitment rate of 0.8% for NHS inpatients and 211 healthy children over a 1-year period. In total, 55 participants were recruited, 30 to the younger group, of which 77% had never taken a tablet before. 84% of the 25 older children had previously taken a tablet. All participants attempted to swallow the smallest sized tablet. The children aged 4-8 years found the larger tablets easier to swallow, however the older children found little difference between the tablet sizes. The younger children required more water to swallow each tablet size compared with the older children where an increasing volume of water was consumed as tablet size increased. Taste was rated highly for both age groups. The 8 mm tablets were deemed the most acceptable tablet size by all participants. CONCLUSION: Tablets are potentially an acceptable formulation for children aged 4-12 years. Most children aged 4-8 years who attempted to swallow tablets successfully did so. Recruitment of NHS inpatients to medicine acceptability studies is challenging, however, recruitment of children of staff proved an effective strategy. Valuable lessons have been learnt from this feasibility study which will inform the design of a larger definitive trial.

A rapid and sensitive HPLC-MS method for the detection of plasma and cellular rifampicin.

Rifampicin is active against both intracellular and extracellular Mycobacterium tuberculosis. The ability to measure rifampicin drug concentrations in both plasma and in cells may be useful in evaluating the suitability of dosage regimens for populations and individuals. Here a novel simple, precise and accurate method for the quantification of rifampicin in both cells and plasma is reported. Sample proteins were precipitated with acetonitrile containing the internal standard and then diluted with water. Aliquots of supernatant were then injected into the HPLC-MS system for chromatographic separation and detection. Rifampicin calibration curves encompassed concentrations from 100 to 12,800 ng/mL. Intra- and inter-assay precision and accuracy were determined using low, medium and high concentration quality control samples and was found to be within 10% in all cases. Rifampicin concentrations were found to be unaffected by freeze-thaw cycles, but were significantly affected by heat-inactivation (58 degrees C, 40 min). This assay was successfully utilised to determine the pharmacokinetic profile of rifampicin in plasma and peripheral blood mononuclear cells (PBMC) in 8 tuberculosis patients receiving rifampicin over an 8h period.