Corrosion leads to substantial economic losses, particularly in the industrial sector, underscoring the importance of effective preventive strategies. Using expired pharmaceuticals as corrosion inhibitors for copper in acidic environments presents several advantages, such as cost-effectiveness, lower toxicity compared to traditional inhibitors, and the added benefit of reducing pharmaceutical waste through recycling. This study examines the impact of inhibitor concentration, immersion time, and temperature on copper corrosion in a sulfuric acid environment, assessed through mass loss measurements. The findings indicate that inhibition efficiency increases with higher inhibitor concentrations but decreases with rising temperatures. In a 0.5 M sulfuric acid solution, expired pharmaceuticals demonstrated an inhibition efficiency of 97.67% at a 1% (V/V) concentration. The study also includes the calculation of activation energy, activation enthalpy, activation entropy, free energy of adsorption, adsorption enthalpy, and adsorption entropy. The adsorption of the inhibitor onto the copper surface followed the Langmuir adsorption isotherm. Additionally, Scanning Electron Microscopy (SEM) provided visual confirmation of the adsorption of expired pharmaceuticals on the copper surface.