RevitaLash® Advanced Eyelash Conditioner has been carefully formulated by an Ophthalmologist and has been tested by independent research laboratories to affirm that it is safe and non-irritating. However, as with any cosmetic, some people may be allergic to one or more ingredients. In order to reduce the potential for irritation, apply a thin line of RevitaLash® Advanced Eyelash Conditioner on clean, dry eyelashes above the lash line, once each day or night. Let dry completely before applying additional beauty products. Do not over apply.