Lichenoid drug eruption is a lichenoid skin eruption caused by certain drugs and compounds, and can be similar to lichen planus. A 51-year-old man who had taken antihypertensive drugs (enalapril, dilazep dihydrochloride) and cholesterol lowering drug (atorvastatin) for 4 years had received allopurinol for asymptomatic hyperuricemia for 4 months. He developed pruritic erythematous papules and plaques with silvery scales on the face, trunk and extremities after taking allopurinol for 3 months. He had no fever, no eosinophilia and no systemic abnormalities. Histopathologic findings showed hyperkeratosis, parakeratosis, hypergranulosis, band-like lymphohistiocytic infiltration and perivascular lymphohistiocytic infiltration in the dermis, which were compatible with lichenoid drug eruption. The skin rashes disappeared after he stopped taking allopurinol and was treated with steroids.
Allopurinol ; Antihypertensive Agents ; Cholesterol ; Dermis ; Dilazep ; Drug Eruptions ; Enalapril ; Eosinophilia ; Exanthema ; Extremities ; Fever ; Humans ; Hyperuricemia ; Lichen Planus ; Middle Aged ; Parakeratosis ; Skin ; Steroids ; Weights and Measures