Comparative Evaluation of Marketed Paracetamol Tablet Brands

Abstract

Background: The therapeutic reliability of immediate-release solid dosage forms is critically dependent on both their physicochemical quality attributes and the kinetics of in-vitro drug release under physiologically relevant conditions. Paracetamol (acetaminophen) remains among the most widely dispensed analgesics and antipyretics globally, yet inter-brand variability in formulation composition and manufacturing processes may influence dissolution behaviour and, consequently, clinical performance. Objective: This study aimed to conduct a systematic comparative evaluation of three commercially available Paracetamol 500 mg immediate-release tablet brands (Brand A, B, and C) procured from the Indian pharmaceutical market, assessing both compendial quality parameters and multimedia in-vitro dissolution profiles across multiple simulated gastrointestinal pH environments. Methods: Physical quality evaluation encompassed weight variation, tablet thickness, hardness, friability, and disintegration time, conducted in accordance with Indian Pharmacopoeia (IP) guidelines. Dissolution testing was performed using IP Apparatus II (Paddle) at 37 ± 0.5°C and 50 rpm in four dissolution media, Purified Water, 0.1N HCl, pH 4.5 Acetate Buffer, and pH 5.8 Phosphate Buffer with spectrophotometric
quantification at 247 nm. Results: All three brands complied with IP weight variation limits (± 5%). Inter-brand differences were observed in hardness (7.20–11.40 kg/cm²), friability (0.13–0.85%), and disintegration time (40 seconds to 3 minutes 06 seconds). In all four-dissolution media, all brands released ≥ 80% of the labelled drug content within 30 minutes, fulfilling the IP dissolution criterion. Brand C, characterized by the highest friability and shortest disintegration time, consistently exhibited the most rapid dissolution profile. Brand B demonstrated the most uniform release pattern, while Brand A achieved robust complete dissolution with the highest structural
integrity. Conclusion: The study establishes a demonstrable correlation between physical formulation parameters, particularly friability and disintegration behaviour and in-vitro dissolution kinetics. Multimedia testing confirmed that the dissolution profiles of all three brands are largely pH-independent, attributable to paracetamol's inherently high aqueous solubility. All evaluated brands satisfy IP compendial standards and may be considered pharmaceutically equivalent and therapeutically interchangeable.