We present the synthesis and comprehensive evaluation of a novel 2‐oxazoline‐based polymer (polyPhOx) functionalized with phenyl groups, designed for the efficient adsorption of pharmaceutical contaminants from aqueous solutions. Employing living polymerization techniques (CROP) with two distinct initiators, we optimize reaction parameters including time, temperature, and initiator concentration. The rigorous characterization of the obtained polymer is depicted as well as the demonstration of its significant binding capacity for various pharmaceuticals, exploiting π–π and electrostatic interactions to achieve superior adsorption efficiency. Adsorption experiments are performed using high concentrations of model pharmaceuticals, including aspirin, ibuprofen, metoclopramide, pyramidone, oestradiol, and indomethacin, in hydroalcoholic solutions. Initial investigations confirm polyPhOx's exceptional efficacy, particularly with hydrophobic compounds such as oestradiol, achieving adsorption capacities of up to 56.67 mg g−1. Further validation in real environmental samples highlights the polymer's practical applicability, showing substantial removal rates even under complex matrix conditions and bringing hope for effective water purification solutions. Remarkably, polyPhOx retains high adsorption performance after 10 cycles, underscoring its potential for sustainable and cost‐effective water purification. This study not only introduces a promising material for environmental remediation but also demonstrates its robustness and reusability, paving the way for advanced wastewater treatment solutions targeting persistent pharmaceutical pollutants.