Keratoconjunctivitis sicca in dogs associated with sulphonamide administration.

This report describes the clinical characteristics of 14 cases of sulphonamide-induced keratoconjuctivitis sicca in dogs. Two drugs, sulphadiazine and salicylazosulphapyridine, were associated with the disease. It is recommended that Schirmer Tear Test be performed regularly when sulphonamides are administered long term to dogs. The hypothesis that a nitrogen-containing pyridine ring is responsible for the lacrimotoxic effect is advanced.