Liquid Chromatographic-Mass Spectrometric Method for Determination of Drug Content Uniformity of Two Commonly Used Dermatology Medications in a Split-Tablet Dosage Form

The study developed and validated a liquid chromatographic-mass spectrometric (LC-MS/MS) method to determine the drug content uniformity of split tablets of two dermatological medications, Lamisil® (terbinafine) and Proscar® (finasteride). Thirty tablets of each medication were analyzed, with tablets split into halves and quarters. The method demonstrated high specificity and sensitivity, with a good linear fit for both drugs. However, the study found that the drug content in split tablets often fell outside the acceptable range, with significant variability in drug distribution. Specifically, 70% of finasteride halves and 85% of quarters, as well as 80% of terbinafine halves and 92.5% of quarters, did not meet the uniformity specifications. The study concluded that non-scored tablets should not be split, especially for medications with significant toxicity, due to the risk of unequal drug distribution.