In an effort to enable wastewater treatment that is more economical and environmentally friendly, alternative adsorbents composed of sewage sludge and fish waste were tested for the removal of pharmaceuticals from aqueous phase. Sewage sludge, fish waste and their homogenized mixtures (90:10, 75:25, 50:50) were carbonized at two temperatures (650 and 950 °C). The obtained materials were extensively characterized in terms of their chemistry and porosity. Adsorption isotherms were used to determine adsorption capacity for 3 model pharmaceuticals: carbamazepine, sulfamethoxazole, and trimethoprim. To simulate the complex environment in the wastewater treatment plant, the adsorption capacity for a multi-component solution, containing equal amounts of all 3 pharmaceuticals was also determined. To elucidate the surface changes during adsorption, analysis by TA-MS, XRD, FT-IR, XRD, SEM and potentiometric titration were conducted. The higher carbonization temperature led to the better performing material, and the composite materials demonstrated a synergistic effect. Amongst the 950 °C carbonized materials, adsorption performance varied by pharmaceutical, as the mechanism of adsorption depended on the characteristics of the pharmaceutical and its interaction with the specific surface chemistry. Although carbamazepine adsorbed in the highest quantity from both single and multi-component solutions, the amount adsorbed decreased for all pharmaceuticals from multi-component solution.