Diaper dermatitis may result from prolonged skin contact with wetness and bacteria. Ammonia plays no apparent role in the generation of diaper dermatitis. Candida albicans frequently contaminates a diaper dermatitis and should be considered present in any diaper dermatitis and should be considered present in any diaper dermatitis known to be present for longer than three days. Topical fluorinated glucocorteroids, boric acid, and mercury-containing preparations should be avoided in the diaper area because of their toxicity.