Remedies for split fingernails include keeping nails clipped, using lotion after washing hands, using mild soaps, wearing gloves when necessary and avoiding the overuse of nail polish remover, notes How Stuff Works. It can take up to six months for split nails to completely heal.
The first step of mending a cracked or split nail is trimming off the damaged part of the fingernail. Using a moisturizing lotion that contains proteins such as keratin and collagen; occlusives, including petroleum, lanolin and mineral oil; and humectants such as lactic acid, glycerin and alpha hydroxy acids can help heal the nail, according to How Stuff Works. Those with split nails should apply lotion to fingernails and cuticles after water exposure and before bed. They can also wear gloves to cut down on water exposure throughout the day, wash hands with mild soap and avoid using nail polish remover more than once per week.