Subconjunctival 5-fluorouracil and herpes simplex keratitis.

We present a case of herpes simplex keratitis that appeared during a period following filtering surgery in which subconjunctival 5-FU was being administered. Although the 5-FU treatment was not halted, 4 days later the keratitis healed. The typical practice of discontinuing 5-FU treatment when these kinds of inflammation occur following filtering surgery may be unwarranted.