The published studies of topical cyclosporin (CyA) therapy in chronic oral lichen planus (OLP) have shown conflicting results. We report an investigator-blinded study of 13 patients with OLP, who were randomly assigned to treatment with CyA (500 mg as a swish-and-spit medication for 5 min three times daily) or a corticosteroid oral paste (triamcinolone acetonide). The duration of treatment was 6 weeks. Thereafter, patients on corticosteroid therapy were treated with CyA. Only slight, transient clinical improvement was observed in both groups after 6 weeks of treatment, compared with baseline. No significant differences could be demonstrated between the two groups. CyA therapy following corticosteroid treatment did not produce any further clinical improvement. During follow-up of the disease for up to 1 year after treatment, neither the CyA nor the corticosteroid group exhibited long-term improvement in disease activity. Contradictory results from earlier reports are discussed.