<unk>  is a iatrogenic cutaneous reaction that occurs immediately after a drug injection. It presents as an immediate, extreme pain around the injection site, with overlying skin rapidly becoming erythematous, violaceous, or blanched ("ischemic pallor") and sometimes with reticular pattern. The reaction eventually leads to variable degrees of necrosis to the skin and underlying tissue. The wound eventually heals, but can lead to atrophic, disfiguring scarring. The reaction is associated with a range of both injection sites and drugs. It was first reported by Freudenthal in 1924 following an injection of bismuth salts for syphilis. Although initial reports were following intramuscular injections, the reaction has since also been reported following subcutaneous, intravenous, and intraarticular injections.<unk>  has been reported to occur with many different drug injections, including: penicillins, local anesthetics (e.g. lidocaine), vaccines (e.g. Dtap), corticosteroids, NSAIDs, and more.
Livedoid dermatitis
Essential dermatitis
Molluscum dermatitis
Blister beetle dermatitis
Actinic prurigo
Phototoxic tar dermatitis
Lacquer dermatitis
Alopecia mucinosa