Do not use the product if the single-dose is damaged. Avoid contact of the single-dose with the eyes. Do not use if you are allergic to any of the components of Opticol GL. Use only once. Since Opticol GL does not contain preservatives, any unused solution immediately after opening the single-dose should be discarded. If you are using other ophthalmic solutions/ointments at the same time, wait about 15 minutes between the application of each product. Opticol GL should be the last one to be administered. Do not apply in case of eye infection or injury. Visual acuity may be temporarily reduced after application; do not drive or use machinery until your vision returns to normal. Opticol GL should not be used after the expiration date indicated on each single-dose and on the outer packaging. Opticol GL contains phosphate buffer. In case of prolonged use and corneal dysfunction, Opticol GL may cause the precipitation of calcium salts in the cornea.