From January 1990 to December 1993, 23 adults were hospitalized at our institution for treatment of foot infections that occurred following nail puncture wounds. All 23 patients had cellulitis, and 14 had signs of osteochondritis on a roentgenogram or a 99mTc bone scan. After undergoing surgical intervention that consisted of debridement, drainage of the pus, and exploration of the bones, patients received intravenous ciprofloxacin (400 mg b.i.d.) for 24 hours, followed by an oral regimen (750 mg b.i.d.), Nine patients with cellulitis received oral therapy for 7 days, and the 14 patients with osteochondritis received oral therapy for 14 days. Isolates that were recovered included Pseudomonas aeruginosa (18 patients) and Staphylococcus aureus (2 patients); one patient had a mixed infection, and in two cases no pathogens were recovered. All of the isolates were susceptible to ciprofloxacin. All patients were cured, and none had reinfection. Our results show that foot infection following a nail puncture wound may be treated with oral ciprofloxacin (750 mg b.i.d.) for 7–14 days, provided that surgery is performed first.