Of 163 patients with intertrochanteric hip fractures 87 received 2 g dicloxacillin and 240 mg of gentamicin preoperatively, and 76 patients had no antibiotic prophylaxis. Preoperative antibiotic prophylaxis was not shown to have any significant effect on wound infections. However, 16 reversible and 1 irreversible cases of kidney toxicity were found among patients receiving antibiotic prophylaxis, whereas there were only four cases of reversible kidney damage among the patients not receiving antibiotics.