Nail damage secondary to nail polishes (enamel, base coats, or top coats) occurs most commonly in the form of irritant and/or allergic contact dermatitis, which can also be spread to other regions of the body on the fingertips. Within the nail apparatus, these reactions often result in onycholysis, paronychia, and nail fold dermatitis.

Other manifestations of nail polish damage include discoloration and keratin granulations. Yellow staining of the nail may occur when polishes are worn for extended periods of time, particularly dark-hued ones. After a while, the dyes leach out of the varnish and penetrate the nail plate too deeply to be removed by conventional solvents. Keratin granulations are superficial white patches and striations that result when fresh coats of enamel are applied over old enamel for several weeks. Superficial friability resembling white superficial onychomycosis develops.

Damage done to the nail apparatus by the application of lacquers is primarily a cosmetic problem. There may be associated pain or pruritus when reactions are severe. These disorders are usually self-limiting and resolve with identification and avoidance of the inciting agent.