In order to reduce corneal complications in 27 glaucomatous eyes that underwent trabeculectomy and postoperative subconjunctival injection of 5-fluorouracil we tried 1) a low-dose administration of 5-fluorouracil and 2) a modified subconjunctival injection technique. The mean total 5-fluorouracil dose was 18.0 +/- 6 mg. A life-table analysis showed a success rate, at 15 months, of 78% (+/- 7 S.E.). Four of the 27 eyes (13%) had corneal complications, limited to punctate keratopathy, with no corneal epithelial defects and/or abrasions. Our study shows that corneal complications decreased when the contact between 5-fluorouracil and the ocular surface was reduced.