Variability in tablet fragment weights when splitting unscored cyclobenzaprine 10 mg tablets.

<bold>Objective: </bold>To determine the weight variation and calculated dosing variability of tablet fragments upon splitting unscored cyclobenzaprine hydrochloride 10 mg tablets using two common tablet splitting devices.<bold>Design: </bold>Comparative pharmaceutics study.<bold>Setting: </bold>Pharmacy school laboratory.<bold>Participants: </bold>Not applicable.<bold>Interventions: </bold>Unscored cyclobenzaprine hydrochloride 10 mg tablets from one generic manufacturer were split with a tablet splitter or a kitchen knife by a licensed pharmacist and two doctor of pharmacy students (n = 15 tablets for each method per participant).<bold>Main Outcome Measures: </bold>Fragment weights (FWs) were compared with the theoretical weights (TWs), which were calculated as one half of the mean weight of the tablets used in each part of the experiment; means, relative standard deviations (RSDs), and percentages of TW were also calculated.<bold>Results: </bold>The mean weight before splitting the 45 tablets with the tablet splitter was 136.6 +/- 2.1 mg (TW = 68.3 mg). The mean FW after splitting was 67.9 +/- 7.9 mg. The RSD of 11.6% corresponded to a range of 69.4% to 130.2% of the TW and an estimated drug content of the split fragments between 3.47 mg and 6.51 mg. The mean weight before splitting the 45 tablets cut with a kitchen knife was 136.6 +/- 2.0 mg (TW = 68.3 mg). The mean FW was 68.0 +/- 15.7 mg with a RSD of 23.2%, corresponding to a range of 49.9% to 149.5% of the TW and an estimated drug content of the split fragments between 2.49 mg and 7.48<bold>Conclusion: </bold>Tablet fragments obtained after splitting this generic cyclobenzaprine 10 mg product varied considerably in weight and estimated drug content. Accordingly, splitting cyclobenzaprine 10 mg tablets to achieve 5 mg doses could result in unpredictable dosing and therapeutic response. [ABSTRACT FROM AUTHOR]