Chronic, low-grade endophthalmitis after cataract surgery with intraocular lens (IOL) implantation is often unresponsive to antibiotic therapy, probably because of low drug penetration into the capsular bag. To increase the drug concentration at the infection site, we irrigated the capsular bag with antibiotics. Within 6 weeks, endophthalmitis resolved in three consecutive patients with positive aqueous cultures. Visual acuity improved from finger counting or less to 20/40 or better in all cases. No recurrence was seen in the 12 to 19 month follow-up. Antibiotic irrigation of the capsular bag can resolve chronic, low-grade endophthalmitis in culture-positive patients unresponsive to the same drugs administered by other routes, including conventional intraocular injection. With this approach there is minimal surgical trauma and the IOL is retained.