Photo-onycholysis induced by doxycycline: a new clinical feature

Photo-onycholysis is a rare complication of tetracyclines. Three clinical subtypes are usually reported. In type I, several nails are often involved and the separated portion of the nail is half-moon-shaped with proximal convexity. In type II, only one nail is involved and there is a proximal notch due to the concentration of ultraviolet rays. Type III is medio-ungueal, away from distal end and lateral folds of the nail. We report a new form of photo-onycholysis induced by doxycycline resembling the latter subtype. In fact there is no involvement of the distal or disto-lateral end of the nail but the separation of the nail starts from the proximal fold. As far as we know, such a clinical feature has not been reported before