Careprost drops is used for eyelash growth but many time it is also advised to treat glaucoma in the eyes. Careprost is based in bimatoprost chemical and all the work is carried out by this chemical. If you are wearing lenses then you must first take it out and then use careprost drops. And yes wash your hands before applying careprost drops.
https://www.icareprost.com/bimatoprost/