Fourteen patients with hereditary angioneurotic oedema (Quincke' oedema) treated for an average period of 6 years (ranging from 15 months to 8 years) with tranexamic acid were given an ophthalmological examination in order to reveal any possible toxic damages caused by the treatment. As large doses of tranexamic acid given to animals have been shown to result in retinal degeneration, the examination was focused on checking the retinal function. A complete ophthalmic examination revealed no toxic effects in the eyes of any of the patients. No retinal damages were found that could have been caused by the tranexamic acid. The central corneal thickness was normal.