Refresh optive advanced sensitive protects your natural tears with a lipid-enhanced drop to reduce tear evaporation. Yet these advanced drops offer the comfort and low blur of water-like (aqueous) drops. Preservative free formula.lipid enhanced lubricant eye drop requires no shaking prior to use. Refresh optive advanced sensitive lubricant eye drops come in sterile, single use vials you can take with you anywhere. They are safe to use as often as needed. Features:preservative freesingle use droppers you can take anywherelubricate for moisturizing dry eye reliefhydrate the eye surface cellsprotect your natural tears by helping reduce tear evaporation should you require consultation with a pharmacist, you maycontact our well.ca pharmacist. Please read the label, warnings and inserts provided by the manufacturer and consult your healthcare professional when purchasing medications or natural health products to be sure the product is right for you.