Comparison of a novel fast-dissolving acetaminophen tablet formulation (FD-APAP) and standard acetaminophen tablets using gamma scintigraphy and pharmacokinetic studies

Context: Acetaminophen (paracetamol, APAP) is widely used to relieve mild-to-moderate pain and reduce fever. Absorption of the drug can be impacted by dosage form; this may have implications for pain relief in some individuals, potentially accounting for suboptimal efficacy in analgesia. Objective: To assess the disintegration and dissolution of a new fast-dissolving acetaminophen tablet formulation (FD-APAP) and the impact on pharmacokinetic and pharmacodynamic parameters. Materials and methods: Two randomized, single-center, open-label, single-dose, two-way crossover studies in healthy subjects to compare FD-APAP (2 × 500 mg tablets) with standard acetaminophen (2 × 500 mg tablets). Gamma scintigraphy was used to assess tablet disintegration (Study 1, N = 24), and plasma profiles were evaluated in the fasted state (Study 2, N = 40). Results: In Study 1, the mean time to complete disintegration (12.9 vs. 69.6 min, P