Tablet splitting and weight uniformity of half-tablets of 4 medications in pharmacy practice

J Pharm Pract. 2012 Aug;25(4):471-6. doi: 10.1177/0897190012442716. Epub 2012 Apr 27.

Abstract

Background: Tablet splitting is a common practice for multiple reasons including cost savings; however, it does not necessarily result in weight-uniform half-tablets.

Objectives: To determine weight uniformity of half-tablets resulting from splitting 4 products available in the Jordanian market and investigate the effect of tablet characteristics on weight uniformity of half-tablets.

Methods: Ten random tablets each of warfarin 5 mg, digoxin 0.25 mg, phenobarbital 30 mg, and prednisolone 5 mg were weighed and split by 6 PharmD students using a knife. The resulting half-tablets were weighed and evaluated for weight uniformity. Other relevant physical characteristics of the 4 products were measured.

Results: The average tablet hardness of the sampled tablets ranged from 40.3 N to 68.9 N. Digoxin, phenobarbital, and prednisolone half-tablets failed the weight uniformity test; however, warfarin half-tablets passed. Digoxin, warfarin, and phenobarbital tablets had a score line and warfarin tablets had the deepest score line of 0.81 mm.

Conclusion: Splitting warfarin tablets produces weight-uniform half-tablets that may possibly be attributed to the hardness and the presence of a deep score line. Digoxin, phenobarbital, and prednisolone tablet splitting produces highly weight variable half-tablets. This can be of clinical significance in the case of the narrow therapeutic index medication digoxin.

MeSH terms

  • Anti-Arrhythmia Agents / chemistry
  • Anti-Arrhythmia Agents / standards
  • Anti-Inflammatory Agents / chemistry
  • Anti-Inflammatory Agents / standards
  • Anticoagulants / chemistry
  • Anticoagulants / standards
  • Cost Savings
  • Digoxin / chemistry
  • Dose-Response Relationship, Drug
  • Drug Compounding
  • Humans
  • Hypnotics and Sedatives / chemistry
  • Hypnotics and Sedatives / standards
  • Jordan
  • Pharmaceutical Preparations / chemistry
  • Pharmaceutical Preparations / standards*
  • Phenobarbital / chemistry
  • Phenobarbital / standards
  • Prednisolone / chemistry
  • Prednisolone / standards
  • Quality Control
  • Reproducibility of Results
  • Tablets / chemistry
  • Tablets / standards*
  • Warfarin / chemistry

Substances

  • Anti-Arrhythmia Agents
  • Anti-Inflammatory Agents
  • Anticoagulants
  • Hypnotics and Sedatives
  • Pharmaceutical Preparations
  • Tablets
  • Warfarin
  • Digoxin
  • Prednisolone
  • Phenobarbital