Scleritis and other ocular side effects associated with pamidronate disodium

PURPOSE: To evaluate reported cases of scleritis and other ocular side effects associated with pamidronate disodium, with emphasis on previously unreported cases of scleritis. DESIGN: Observational case series. METHODS: Case reports from the National Registry of Drug-Induced Ocular Side Effects (Casey Eye Institute), the Food and Drug Administration, the World Health Organization, and the literature were reviewed to determine possible adverse ocular side effects associated with pamidronate disodium. The World Health Organization's Causality Assessment Guide was used to categorize an adverse drug reaction. RESULTS: Seventeen cases of unilateral scleritis and one case of bilateral scleritis occurred, usually within 6 hours to 2 days after intravenous pamidronate disodium. Six patients had positive rechallenge testing with the scleritis occurring after a repeat drug exposure. Other ocular side effects with positive rechallenge data, associated with pamidronate disodium, include blurred vision, nonspecific conjunctivitis, ocular pain, bilateral anterior uveitis, and episcleritis. CONCLUSIONS: This is the first report, with rechallenge data, of any drug causing scleritis. Pamidronate disodium can cause vision-threatening diseases, which may require discontinuing the drug in some uveitis cases and, in this series, all cases of scleritis.