A Comprehsensive Review on Analytical Method Development and Validation for Naproxen and Paracetamol in Bulk and Pharmaceutical Dosage Forms

The treatment of pain, inflammation, and fever, naproxen and paracetamol are commonly used analgesic and antipyretic medications that can be taken alone or in combination. For quality assurance, regulatory compliance, and therapeutic efficacy, these medications must be accurately quantified in bulk and pharmaceutical dosage forms. With a particular focus on reversed-phase high-performance liquid chromatography (RP-HPLC) and ultraviolet (UV) spectrophotometric techniques for the quantification of naproxen and paracetamol, this study critically reviews current advancements in analytical procedures. Key chromatographic parameters (stationary phase, mobile phase composition, flow rate, detection wavelength, and retention times), ICH-recommended validation parameters (linearity, accuracy, precision, specificity, robustness, LOD, and LOQ), and applications to commercial formulations are compiled from published research. Additionally covered are simultaneous estimating techniques for combinations such paracetamol–ibuprofen, sumatriptan–naproxen, and paracetamol–naproxen. The methods under consideration exhibit simplicity, sensitivity, accuracy (recoveries usually 97–102%), and precision (RSD ≤ 2%), which qualify them for regular quality monitoring. Future directions toward greener, faster, and stability-indicating methodologies are discussed, along with the shortcomings of current systems.