We used an experimental model of proliferative vitreoretinopathy (PVR) and cell-induced traction retinal detachment to study the therapeutic value of six cytotoxic drugs (actinomycin C, colchicine, cytosine arabinoside hydrochloride, 5-fluorodeoxyuridine, vinblastine sulfate, and daunomycin). Pigmented rabbits were injected with 2.5 X 10(5) cultured homologous dermal fibroblasts. At the same time, cytotoxic drugs were injected into the vitreous in an attempt to inhibit cellular proliferation. The sensitivity of the cells to the drug was also tested in vitro before injection. Daunomycin at a dose of 10 nmol per eye stopped cellular proliferation and subsequent traction retinal detachment in vivo. The electroretinogram (ERG) showed no evidence of drug-induced retinal toxicity with this dose of daunomycin. No alteration in frequency or severity of vitreal membranes and retinal detachment was observed after injection of equivalent doses of the other drugs.