Renal failure after taking cefadroxil may be caused by drug overdose, or it may be caused by itself suffering from acute interstitial nephritis, urinary disorders and other reasons. 1. Drug overdose: overdose of cefadroxil, there can be proximal tubular epithelial cell damage, renal tubular degeneration and necrosis, proteinuria and blood urea nitrogen increase, and in severe cases, renal failure can occur. 2. Acute interstitial nephritis: it is a group of diseases that cause renal interstitial damage, and the etiology is very complex. It may be caused by renal infectious diseases, nephrotoxic substances, X-ray prolonged irradiation, various drugs poisoning, etc. Patients may have renal interstitial damage, which may cause renal failure. 3. Urinary obstruction: it may be due to severe hypokalemia, taking ganglion blockers and so on can cause urinary obstruction, retrograde infection can occur, which in turn causes acute renal failure. It is recommended that patients with renal failure after taking cefadroxil go to the hospital in time, and follow the doctor’s instructions after clarifying the cause of the disease, so as to avoid delaying the condition.