<p>The increasing presence of pharmaceutical residues such as paracetamol in aquatic environments highlights the need for sustainable and efficient treatment strategies. In this study, activated carbon derived from Spirulina biomass was evaluated as a bio-based and environmentally friendly adsorbent for paracetamol removal from aqueous solutions. The adsorption performance was systematically investigated and compared with commercial activated carbon to assess the practical potential of microalgae-derived materials. Structural characterization indicated that Spirulina-derived activated carbon exhibits a high surface area and a predominantly mesoporous structure, enhancing accessibility to adsorption sites. Adsorption experiments revealed that paracetamol removal was strongly influenced by solution pH, contact time, and adsorbent dosage, which were optimized using response surface methodology. Under the optimized experimental conditions, a maximum paracetamol removal efficiency of 99.65% was obtained within the studied parameter range. Equilibrium data were best described by the Langmuir isotherm model, indicating monolayer adsorption with a maximum adsorption capacity (Q_max) of 34.28&#xa0;mg/g, which falls within the range reported for many previously studied bio-based adsorbents. The enhanced adsorption performance was attributed to the favorable pore structure and surface characteristics of the Spirulina-derived carbon. Overall, the findings suggest that Spirulina-derived activated carbon may serve as a promising bio-based alternative for pharmaceutical adsorption under controlled laboratory conditions. This study focuses on the removal of paracetamol as a representative pharmaceutical compound to evaluate the adsorption potential of Spirulina-derived activated carbon. While real wastewater systems contain a wide range of emerging contaminants, the findings of this work are intended to provide insight into pharmaceutical removal rather than proposing a comprehensive wastewater treatment solution.</p>