Does splitting a tablet obtain an accurate dose? A systematic review and meta‐ analysis

Abstract

Background Tablet splitting is a widely prevalent practice resulting from the need to alter doses into two or more parts and optimise medicine in individual patients. If a tablet is split unequally problems may arise. Aim The aim of the study was to summarise the literature measuring the effect of tablet splitting on dose accuracy. Method MEDLINE, EMBASE, CINAHL and Cochrane were searched and studies published prior to January 2020 investigating the effect of splitting tablets on dose accuracy were included. Studies investigating any drug, where the tablet was split, were potentially eligible. Two independent reviewers conducted the screening and extracted the data. Meta‐analyses assessing the effect of tablet splitting on dose accuracy were performed. (Study registration: PROSPERO CRD42018106252). Results Of 25 included studies, 16 examined the effect of tablet splitting on weight of the tablet, one on drug concentration and eight examined both. Meta‐analysis found small variation between split tablets (0.87% weight variation, 95% confidence interval 0.63%–1.11% and 0.24% drug content variation, 95% confidence interval 0.06%–0.43%). There was some inconsistency across trial results for weight but not for drug content variation (I2 50% and I2 1%, respectively). Splitting method and tablet characteristics were predictors of accuracy. Conclusion Although tablet splitting may influence dose accuracy, this analysis suggests that the weight and drug content variation is minimal, regardless of method and tablet characteristics. Additional studies, such as those examining drug plasma concentrations and effect on patient health outcomes for example blood pressure and cholesterol levels, are needed to better understand the role of tablet splitting on dose accuracy.