Onycholysis (detachment of the nail plate from the nail bed) starts in the central or lateral
portion of the nail plate free margin, progresses proximally and can even involve the
whole nail. The onycholytic area looks whitish because of the presence of air under the
detached nail plate. It may occasionally show a greenish or brown discoloration due to
colonization of the onycholytic space by chromogenic bacteria    (Pseudomonas
aeruginosa), moulds or yeasts. Onycholysis may be idiopathic or represent a symptom of
numerous diseases (such as psoriasis, onychomycosis or contact dermatitis) or drug
reactions.
Depending on the cause of the complaint (e.g. disease or impaired peripheral
circulation), appropriate local treatment, systemic treatment or both is prescribed. The
detached nail should be clipped away and a mild antibacterial solution (thymol 4% in
chloroform) should be applied on the exposed nail bed at night. Pseudomonas infection
is easily treated by using sodium hypochlorite solution or 2% acetic acid. Accurate
drying of the fingers after hand washing is necessary. A hair dryer may be useful for this
purpose.