Fixed drug eruption secondary to etoricoxib.

Fixed drug eruptions (FDE) are adverse cutaneous drug reactions and a form of delayed type 4 hypersensitivity reaction characterised by recurrent lesions at the same site each time a specific drug is taken. They most commonly result in cutaneous lesions presenting as an erythematous round or oval macule or plaque. FDEs have rarely been reported to affect oral mucous membranes and tend to have a bullous or aphthous-like appearance with erythema. Almost half of patients report an increase in the severity of symptoms with prolonged exposure to the offending medication. The most commonly attributed classes of drug are antibiotics (tetracyclines and sulphonamides) alongside non-steroidal anti-inflammatory drugs. Cutaneous adverse reactions to etoricoxib, a highly selective COX-2 inhibitor, have been reported. Here we describe an adverse reaction restricted to the oral mucosa.