How does aspirin acidify urine?

Aspirin, or acetylsalicylic acid, can acidify urine by increasing the excretion of hydrogen ions (H+) and promoting the reabsorption of bicarbonate (HCO3-) in the kidneys. When aspirin is metabolized, it generates salicylic acid, which can dissociate to release H+ ions, lowering the pH of urine. Additionally, aspirin's effect on renal function can alter the acid-base balance, leading to a more acidic urine overall. This acidification can influence the solubility and excretion of certain drugs and metabolites.