Between mid-May and mid-July 1987 we performed a prospective crossover study of two unit-dose preservative-free artificial tear solutions, 1.4% polyvinyl alcohol (Refresh) and 0.1% sodium hyaluronate (Hylorin) in 14 female patients with severe dry eye syndrome. The patients were examined before treatment and after each of two trials with both products. A significant reduction in the mean score for dry-eye-induced keratitis (p = 0.001) and for mucous strands (p = 0.03) was observed following the second of two trials with sodium hyaluronate. A significant reduction in the mean score for burning and irritation was observed with both solutions (p = 0.009). We believe that the elimination of preservatives from artificial tear preparations may substantially reduce the iatrogenic effects of these frequently applied medications.