Aim: Although propranolol is widely used in the treatment of infantile hemangiomas, the standard 40 mg tablet needs to be fractioned to obtain 10 mg parts, with even lower doses (i.e., 2-3 mg/kg/day divided into 2-3 daily doses) required in infants. This study evaluated the weight and dose uniformity in split quarters of propranolol tablets.
Methods: Twenty pharmacy students split 70 propranolol tablets by using a kitchen knife in order to obtain 200 quarters, which were considered integral and adequate for administration. Intact tablets and quarters were weighed. The content of propranolol in tablet quarters was determined on 200 quarters by using high performance liquid chromatography.
Results: Overall, 265 parts (94.6%) were integral and 213 (76.1%) were considered as adequate for administration. The mean (± standard deviation) weight of quarters judged as suitable and non-suitable for administration was 49.56 ± 5.27 mg and 46.24 ± 7.53 mg, respectively. Splitting caused a mean weight loss in each tablet of 2.97 ± 2.91 mg (median 2.06 mg). The percentage of quarters with weight lower than theoretical was 55.88%, and the remaining weighted more than expected. The mean propranolol content in quarters was 9.52 ± 0.96 mg (median 9.42 mg, range 7.36-12.23 mg) and 42% of quarters were out of the ± 10% acceptance range.
Conclusion: The manual splitting of propranolol 40 mg tablets produced a significant proportion of quarters not suitable for administration in children or with a weight and/or an active concentration outside of the required range. The availability of a pediatric oral solution of propranolol will reduce the risk of incorrect dosing.