Method of preparing an eye drop of cyclosporine

A process for preparing a collyrium of cyclosporin A in the form of an emulsion or of a lipophilic / hydrophilic microemulsion in which the lipophilic phase, so oil contains cyclosporin A, characterized in that it comprises at least the steps of a) removing at least 99% by weight of ethanol contained in the oily solution of cyclosporin a, b) diluting the aqueous solution concentrate obtained in step a), c) performing an emulsion or a microemulsion by mixing with stirring the concentrated oily solution obtained in step a) with the dilute aqueous solution obtained in step b), d) packaging sterile eye drops obtained in packaging suitable for ophthalmic use.